# new _(value) → {Object}
Creates a lodash object which wraps value to enable implicit method
chain sequences. Methods that operate on and return arrays, collections,
and functions can be chained together. Methods that retrieve a single value
or may return a primitive value will automatically end the chain sequence
and return the unwrapped value. Otherwise, the value must be unwrapped
with _#value.
Explicit chain sequences, which must be unwrapped with _#value, may be
enabled using _.chain.
The execution of chained methods is lazy, that is, it's deferred until
_#value is implicitly or explicitly called.
Lazy evaluation allows several methods to support shortcut fusion. Shortcut fusion is an optimization to merge iteratee calls; this avoids the creation of intermediate arrays and can greatly reduce the number of iteratee executions. Sections of a chain sequence qualify for shortcut fusion if the section is applied to an array and iteratees accept only one argument. The heuristic for whether a section qualifies for shortcut fusion is subject to change.
Chaining is supported in custom builds as long as the _#value method is
directly or indirectly included in the build.
In addition to lodash methods, wrappers have Array and String methods.
The wrapper Array methods are:
concat, join, pop, push, shift, sort, splice, and unshift
The wrapper String methods are:
replace and split
The wrapper methods that support shortcut fusion are:
at, compact, drop, dropRight, dropWhile, filter, find,
findLast, head, initial, last, map, reject, reverse, slice,
tail, take, takeRight, takeRightWhile, takeWhile, and toArray
The chainable wrapper methods are:
after, ary, assign, assignIn, assignInWith, assignWith, at,
before, bind, bindAll, bindKey, castArray, chain, chunk,
commit, compact, concat, conforms, constant, countBy, create,
curry, debounce, defaults, defaultsDeep, defer, delay,
difference, differenceBy, differenceWith, drop, dropRight,
dropRightWhile, dropWhile, extend, extendWith, fill, filter,
flatMap, flatMapDeep, flatMapDepth, flatten, flattenDeep,
flattenDepth, flip, flow, flowRight, fromPairs, functions,
functionsIn, groupBy, initial, intersection, intersectionBy,
intersectionWith, invert, invertBy, invokeMap, iteratee, keyBy,
keys, keysIn, map, mapKeys, mapValues, matches, matchesProperty,
memoize, merge, mergeWith, method, methodOf, mixin, negate,
nthArg, omit, omitBy, once, orderBy, over, overArgs,
overEvery, overSome, partial, partialRight, partition, pick,
pickBy, plant, property, propertyOf, pull, pullAll, pullAllBy,
pullAllWith, pullAt, push, range, rangeRight, rearg, reject,
remove, rest, reverse, sampleSize, set, setWith, shuffle,
slice, sort, sortBy, splice, spread, tail, take, takeRight,
takeRightWhile, takeWhile, tap, throttle, thru, toArray,
toPairs, toPairsIn, toPath, toPlainObject, transform, unary,
union, unionBy, unionWith, uniq, uniqBy, uniqWith, unset,
unshift, unzip, unzipWith, update, updateWith, values,
valuesIn, without, wrap, xor, xorBy, xorWith, zip,
zipObject, zipObjectDeep, and zipWith
The wrapper methods that are not chainable by default are:
add, attempt, camelCase, capitalize, ceil, clamp, clone,
cloneDeep, cloneDeepWith, cloneWith, conformsTo, deburr,
defaultTo, divide, each, eachRight, endsWith, eq, escape,
escapeRegExp, every, find, findIndex, findKey, findLast,
findLastIndex, findLastKey, first, floor, forEach, forEachRight,
forIn, forInRight, forOwn, forOwnRight, get, gt, gte, has,
hasIn, head, identity, includes, indexOf, inRange, invoke,
isArguments, isArray, isArrayBuffer, isArrayLike, isArrayLikeObject,
isBoolean, isBuffer, isDate, isElement, isEmpty, isEqual,
isEqualWith, isError, isFinite, isFunction, isInteger, isLength,
isMap, isMatch, isMatchWith, isNaN, isNative, isNil, isNull,
isNumber, isObject, isObjectLike, isPlainObject, isRegExp,
isSafeInteger, isSet, isString, isUndefined, isTypedArray,
isWeakMap, isWeakSet, join, kebabCase, last, lastIndexOf,
lowerCase, lowerFirst, lt, lte, max, maxBy, mean, meanBy,
min, minBy, multiply, noConflict, noop, now, nth, pad,
padEnd, padStart, parseInt, pop, random, reduce, reduceRight,
repeat, result, round, runInContext, sample, shift, size,
snakeCase, some, sortedIndex, sortedIndexBy, sortedLastIndex,
sortedLastIndexBy, startCase, startsWith, stubArray, stubFalse,
stubObject, stubString, stubTrue, subtract, sum, sumBy,
template, times, toFinite, toInteger, toJSON, toLength,
toLower, toNumber, toSafeInteger, toString, toUpper, trim,
trimEnd, trimStart, truncate, unescape, uniqueId, upperCase,
upperFirst, value, and words
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to wrap in a |
Returns the new lodash wrapper instance.
Example
function square(n) {
return n * n;
}
var wrapped = _([1, 2, 3]);
// Returns an unwrapped value.
wrapped.reduce(_.add);
// => 6
// Returns a wrapped value.
var squares = wrapped.map(square);
_.isArray(squares);
// => false
_.isArray(squares.value());
// => true
Members
# static assign
Assigns own enumerable string keyed properties of source objects to the destination object. Source objects are applied from left to right. Subsequent sources overwrite property assignments of previous sources.
Note: This method mutates object and is loosely based on
Object.assign.
- Since:
- 0.10.0
- See:
-
- _.assignIn
Example
function Foo() {
this.a = 1;
}
function Bar() {
this.c = 3;
}
Foo.prototype.b = 2;
Bar.prototype.d = 4;
_.assign({ 'a': 0 }, new Foo, new Bar);
// => { 'a': 1, 'c': 3 }
# static assign
Assigns own enumerable string keyed properties of source objects to the destination object. Source objects are applied from left to right. Subsequent sources overwrite property assignments of previous sources.
Note: This method mutates object and is loosely based on
Object.assign.
- Since:
- 0.10.0
- See:
-
- _.assignIn
Example
function Foo() {
this.a = 1;
}
function Bar() {
this.c = 3;
}
Foo.prototype.b = 2;
Bar.prototype.d = 4;
_.assign({ 'a': 0 }, new Foo, new Bar);
// => { 'a': 1, 'c': 3 }
# static assign
Assigns own enumerable string keyed properties of source objects to the destination object. Source objects are applied from left to right. Subsequent sources overwrite property assignments of previous sources.
Note: This method mutates object and is loosely based on
Object.assign.
- Since:
- 0.10.0
- See:
-
- _.assignIn
Example
function Foo() {
this.a = 1;
}
function Bar() {
this.c = 3;
}
Foo.prototype.b = 2;
Bar.prototype.d = 4;
_.assign({ 'a': 0 }, new Foo, new Bar);
// => { 'a': 1, 'c': 3 }
# static assignWith
This method is like _.assign except that it accepts customizer
which is invoked to produce the assigned values. If customizer returns
undefined, assignment is handled by the method instead. The customizer
is invoked with five arguments: (objValue, srcValue, key, object, source).
Note: This method mutates object.
- Since:
- 4.0.0
- See:
-
- _.assignInWith
Example
function customizer(objValue, srcValue) {
return _.isUndefined(objValue) ? srcValue : objValue;
}
var defaults = _.partialRight(_.assignWith, customizer);
defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
// => { 'a': 1, 'b': 2 }
# static assignWith
This method is like _.assign except that it accepts customizer
which is invoked to produce the assigned values. If customizer returns
undefined, assignment is handled by the method instead. The customizer
is invoked with five arguments: (objValue, srcValue, key, object, source).
Note: This method mutates object.
- Since:
- 4.0.0
- See:
-
- _.assignInWith
Example
function customizer(objValue, srcValue) {
return _.isUndefined(objValue) ? srcValue : objValue;
}
var defaults = _.partialRight(_.assignWith, customizer);
defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
// => { 'a': 1, 'b': 2 }
# static at
Creates an array of values corresponding to paths of object.
- Since:
- 1.0.0
Example
var object = { 'a': [{ 'b': { 'c': 3 } }, 4] };
_.at(object, ['a[0].b.c', 'a[1]']);
// => [3, 4]
# static at
This method is the wrapper version of _.at.
- Since:
- 1.0.0
Example
var object = { 'a': [{ 'b': { 'c': 3 } }, 4] };
_(object).at(['a[0].b.c', 'a[1]']).value();
// => [3, 4]
# static at
Creates an array of values corresponding to paths of object.
- Since:
- 1.0.0
Example
var object = { 'a': [{ 'b': { 'c': 3 } }, 4] };
_.at(object, ['a[0].b.c', 'a[1]']);
// => [3, 4]
# static at
This method is the wrapper version of _.at.
- Since:
- 1.0.0
Example
var object = { 'a': [{ 'b': { 'c': 3 } }, 4] };
_(object).at(['a[0].b.c', 'a[1]']).value();
// => [3, 4]
# static attempt
Attempts to invoke func, returning either the result or the caught error
object. Any additional arguments are provided to func when it's invoked.
- Since:
- 3.0.0
Example
// Avoid throwing errors for invalid selectors.
var elements = _.attempt(function(selector) {
return document.querySelectorAll(selector);
}, '>_>');
if (_.isError(elements)) {
elements = [];
}
# static attempt
Attempts to invoke func, returning either the result or the caught error
object. Any additional arguments are provided to func when it's invoked.
- Since:
- 3.0.0
Example
// Avoid throwing errors for invalid selectors.
var elements = _.attempt(function(selector) {
return document.querySelectorAll(selector);
}, '>_>');
if (_.isError(elements)) {
elements = [];
}
# static bind
Creates a function that invokes func with the this binding of thisArg
and partials prepended to the arguments it receives.
The _.bind.placeholder value, which defaults to _ in monolithic builds,
may be used as a placeholder for partially applied arguments.
Note: Unlike native Function#bind, this method doesn't set the "length"
property of bound functions.
- Since:
- 0.1.0
Example
function greet(greeting, punctuation) {
return greeting + ' ' + this.user + punctuation;
}
var object = { 'user': 'fred' };
var bound = _.bind(greet, object, 'hi');
bound('!');
// => 'hi fred!'
// Bound with placeholders.
var bound = _.bind(greet, object, _, '!');
bound('hi');
// => 'hi fred!'
# static bind
Creates a function that invokes func with the this binding of thisArg
and partials prepended to the arguments it receives.
The _.bind.placeholder value, which defaults to _ in monolithic builds,
may be used as a placeholder for partially applied arguments.
Note: Unlike native Function#bind, this method doesn't set the "length"
property of bound functions.
- Since:
- 0.1.0
Example
function greet(greeting, punctuation) {
return greeting + ' ' + this.user + punctuation;
}
var object = { 'user': 'fred' };
var bound = _.bind(greet, object, 'hi');
bound('!');
// => 'hi fred!'
// Bound with placeholders.
var bound = _.bind(greet, object, _, '!');
bound('hi');
// => 'hi fred!'
# static bind
Creates a function that invokes func with the this binding of thisArg
and partials prepended to the arguments it receives.
The _.bind.placeholder value, which defaults to _ in monolithic builds,
may be used as a placeholder for partially applied arguments.
Note: Unlike native Function#bind, this method doesn't set the "length"
property of bound functions.
- Since:
- 0.1.0
Example
function greet(greeting, punctuation) {
return greeting + ' ' + this.user + punctuation;
}
var object = { 'user': 'fred' };
var bound = _.bind(greet, object, 'hi');
bound('!');
// => 'hi fred!'
// Bound with placeholders.
var bound = _.bind(greet, object, _, '!');
bound('hi');
// => 'hi fred!'
# static bindAll
Binds methods of an object to the object itself, overwriting the existing method.
Note: This method doesn't set the "length" property of bound functions.
- Since:
- 0.1.0
Example
var view = {
'label': 'docs',
'click': function() {
console.log('clicked ' + this.label);
}
};
_.bindAll(view, ['click']);
jQuery(element).on('click', view.click);
// => Logs 'clicked docs' when clicked.
# static bindAll
Binds methods of an object to the object itself, overwriting the existing method.
Note: This method doesn't set the "length" property of bound functions.
- Since:
- 0.1.0
Example
var view = {
'label': 'docs',
'click': function() {
console.log('clicked ' + this.label);
}
};
_.bindAll(view, ['click']);
jQuery(element).on('click', view.click);
// => Logs 'clicked docs' when clicked.
# static bindKey
Creates a function that invokes the method at object[key] with partials
prepended to the arguments it receives.
This method differs from _.bind by allowing bound functions to reference
methods that may be redefined or don't yet exist. See
Peter Michaux's article
for more details.
The _.bindKey.placeholder value, which defaults to _ in monolithic
builds, may be used as a placeholder for partially applied arguments.
- Since:
- 0.10.0
Example
var object = {
'user': 'fred',
'greet': function(greeting, punctuation) {
return greeting + ' ' + this.user + punctuation;
}
};
var bound = _.bindKey(object, 'greet', 'hi');
bound('!');
// => 'hi fred!'
object.greet = function(greeting, punctuation) {
return greeting + 'ya ' + this.user + punctuation;
};
bound('!');
// => 'hiya fred!'
// Bound with placeholders.
var bound = _.bindKey(object, 'greet', _, '!');
bound('hi');
// => 'hiya fred!'
# static bindKey
Creates a function that invokes the method at object[key] with partials
prepended to the arguments it receives.
This method differs from _.bind by allowing bound functions to reference
methods that may be redefined or don't yet exist. See
Peter Michaux's article
for more details.
The _.bindKey.placeholder value, which defaults to _ in monolithic
builds, may be used as a placeholder for partially applied arguments.
- Since:
- 0.10.0
Example
var object = {
'user': 'fred',
'greet': function(greeting, punctuation) {
return greeting + ' ' + this.user + punctuation;
}
};
var bound = _.bindKey(object, 'greet', 'hi');
bound('!');
// => 'hi fred!'
object.greet = function(greeting, punctuation) {
return greeting + 'ya ' + this.user + punctuation;
};
bound('!');
// => 'hiya fred!'
// Bound with placeholders.
var bound = _.bindKey(object, 'greet', _, '!');
bound('hi');
// => 'hiya fred!'
# static camelCase
Converts string to camel case.
- Since:
- 3.0.0
Example
_.camelCase('Foo Bar');
// => 'fooBar'
_.camelCase('--foo-bar--');
// => 'fooBar'
_.camelCase('__FOO_BAR__');
// => 'fooBar'
# static camelCase
Converts string to camel case.
- Since:
- 3.0.0
Example
_.camelCase('Foo Bar');
// => 'fooBar'
_.camelCase('--foo-bar--');
// => 'fooBar'
_.camelCase('__FOO_BAR__');
// => 'fooBar'
# static ceil
Computes number rounded up to precision.
- Since:
- 3.10.0
Example
_.ceil(4.006);
// => 5
_.ceil(6.004, 2);
// => 6.01
_.ceil(6040, -2);
// => 6100
# static ceil
Computes number rounded up to precision.
- Since:
- 3.10.0
Example
_.ceil(4.006);
// => 5
_.ceil(6.004, 2);
// => 6.01
_.ceil(6040, -2);
// => 6100
# static chain
Creates a lodash wrapper instance with explicit method chain sequences enabled.
- Since:
- 0.1.0
Example
var users = [
{ 'user': 'barney', 'age': 36 },
{ 'user': 'fred', 'age': 40 }
];
// A sequence without explicit chaining.
_(users).head();
// => { 'user': 'barney', 'age': 36 }
// A sequence with explicit chaining.
_(users)
.chain()
.head()
.pick('user')
.value();
// => { 'user': 'barney' }
# static chain
Creates a lodash wrapper instance with explicit method chain sequences enabled.
- Since:
- 0.1.0
Example
var users = [
{ 'user': 'barney', 'age': 36 },
{ 'user': 'fred', 'age': 40 }
];
// A sequence without explicit chaining.
_(users).head();
// => { 'user': 'barney', 'age': 36 }
// A sequence with explicit chaining.
_(users)
.chain()
.head()
.pick('user')
.value();
// => { 'user': 'barney' }
# static chain
Creates a lodash wrapper instance with explicit method chain sequences enabled.
- Since:
- 0.1.0
Example
var users = [
{ 'user': 'barney', 'age': 36 },
{ 'user': 'fred', 'age': 40 }
];
// A sequence without explicit chaining.
_(users).head();
// => { 'user': 'barney', 'age': 36 }
// A sequence with explicit chaining.
_(users)
.chain()
.head()
.pick('user')
.value();
// => { 'user': 'barney' }
# static commit
Executes the chain sequence and returns the wrapped result.
- Since:
- 3.2.0
Example
var array = [1, 2];
var wrapped = _(array).push(3);
console.log(array);
// => [1, 2]
wrapped = wrapped.commit();
console.log(array);
// => [1, 2, 3]
wrapped.last();
// => 3
console.log(array);
// => [1, 2, 3]
# static commit
Executes the chain sequence and returns the wrapped result.
- Since:
- 3.2.0
Example
var array = [1, 2];
var wrapped = _(array).push(3);
console.log(array);
// => [1, 2]
wrapped = wrapped.commit();
console.log(array);
// => [1, 2, 3]
wrapped.last();
// => 3
console.log(array);
// => [1, 2, 3]
# static countBy
Creates an object composed of keys generated from the results of running
each element of collection thru iteratee. The corresponding value of
each key is the number of times the key was returned by iteratee. The
iteratee is invoked with one argument: (value).
- Since:
- 0.5.0
Example
_.countBy([6.1, 4.2, 6.3], Math.floor);
// => { '4': 1, '6': 2 }
// The `_.property` iteratee shorthand.
_.countBy(['one', 'two', 'three'], 'length');
// => { '3': 2, '5': 1 }
# static countBy
Creates an object composed of keys generated from the results of running
each element of collection thru iteratee. The corresponding value of
each key is the number of times the key was returned by iteratee. The
iteratee is invoked with one argument: (value).
- Since:
- 0.5.0
Example
_.countBy([6.1, 4.2, 6.3], Math.floor);
// => { '4': 1, '6': 2 }
// The `_.property` iteratee shorthand.
_.countBy(['one', 'two', 'three'], 'length');
// => { '3': 2, '5': 1 }
# static defaults
Assigns own and inherited enumerable string keyed properties of source
objects to the destination object for all destination properties that
resolve to undefined. Source objects are applied from left to right.
Once a property is set, additional values of the same property are ignored.
Note: This method mutates object.
- Since:
- 0.1.0
- See:
Example
_.defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
// => { 'a': 1, 'b': 2 }
# static defaults
Assigns own and inherited enumerable string keyed properties of source
objects to the destination object for all destination properties that
resolve to undefined. Source objects are applied from left to right.
Once a property is set, additional values of the same property are ignored.
Note: This method mutates object.
- Since:
- 0.1.0
- See:
Example
_.defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
// => { 'a': 1, 'b': 2 }
# static defaults
Assigns own and inherited enumerable string keyed properties of source
objects to the destination object for all destination properties that
resolve to undefined. Source objects are applied from left to right.
Once a property is set, additional values of the same property are ignored.
Note: This method mutates object.
- Since:
- 0.1.0
- See:
Example
_.defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
// => { 'a': 1, 'b': 2 }
# static defaultsDeep
This method is like _.defaults except that it recursively assigns
default properties.
Note: This method mutates object.
- Since:
- 3.10.0
- See:
Example
_.defaultsDeep({ 'a': { 'b': 2 } }, { 'a': { 'b': 1, 'c': 3 } });
// => { 'a': { 'b': 2, 'c': 3 } }
# static defaultsDeep
This method is like _.defaults except that it recursively assigns
default properties.
Note: This method mutates object.
- Since:
- 3.10.0
- See:
Example
_.defaultsDeep({ 'a': { 'b': 2 } }, { 'a': { 'b': 1, 'c': 3 } });
// => { 'a': { 'b': 2, 'c': 3 } }
# static defer
Defers invoking the func until the current call stack has cleared. Any
additional arguments are provided to func when it's invoked.
- Since:
- 0.1.0
Example
_.defer(function(text) {
console.log(text);
}, 'deferred');
// => Logs 'deferred' after one millisecond.
# static defer
Defers invoking the func until the current call stack has cleared. Any
additional arguments are provided to func when it's invoked.
- Since:
- 0.1.0
Example
_.defer(function(text) {
console.log(text);
}, 'deferred');
// => Logs 'deferred' after one millisecond.
# static defer
Defers invoking the func until the current call stack has cleared. Any
additional arguments are provided to func when it's invoked.
- Since:
- 0.1.0
Example
_.defer(function(text) {
console.log(text);
}, 'deferred');
// => Logs 'deferred' after one millisecond.
# static delay
Invokes func after wait milliseconds. Any additional arguments are
provided to func when it's invoked.
- Since:
- 0.1.0
Example
_.delay(function(text) {
console.log(text);
}, 1000, 'later');
// => Logs 'later' after one second.
# static delay
Invokes func after wait milliseconds. Any additional arguments are
provided to func when it's invoked.
- Since:
- 0.1.0
Example
_.delay(function(text) {
console.log(text);
}, 1000, 'later');
// => Logs 'later' after one second.
# static delay
Invokes func after wait milliseconds. Any additional arguments are
provided to func when it's invoked.
- Since:
- 0.1.0
Example
_.delay(function(text) {
console.log(text);
}, 1000, 'later');
// => Logs 'later' after one second.
# static difference
Creates an array of array values not included in the other given arrays
using SameValueZero
for equality comparisons. The order and references of result values are
determined by the first array.
Note: Unlike _.pullAll, this method returns a new array.
- Since:
- 0.1.0
- See:
-
- _.without, _.xor
Example
_.difference([2, 1], [2, 3]);
// => [1]
# static difference
Creates an array of array values not included in the other given arrays
using SameValueZero
for equality comparisons. The order and references of result values are
determined by the first array.
Note: Unlike _.pullAll, this method returns a new array.
- Since:
- 0.1.0
- See:
-
- _.without, _.xor
Example
_.difference([2, 1], [2, 3]);
// => [1]
# static differenceBy
This method is like _.difference except that it accepts iteratee which
is invoked for each element of array and values to generate the criterion
by which they're compared. The order and references of result values are
determined by the first array. The iteratee is invoked with one argument:
(value).
Note: Unlike _.pullAllBy, this method returns a new array.
- Since:
- 4.0.0
Example
_.differenceBy([2.1, 1.2], [2.3, 3.4], Math.floor);
// => [1.2]
// The `_.property` iteratee shorthand.
_.differenceBy([{ 'x': 2 }, { 'x': 1 }], [{ 'x': 1 }], 'x');
// => [{ 'x': 2 }]
# static differenceBy
This method is like _.difference except that it accepts iteratee which
is invoked for each element of array and values to generate the criterion
by which they're compared. The order and references of result values are
determined by the first array. The iteratee is invoked with one argument:
(value).
Note: Unlike _.pullAllBy, this method returns a new array.
- Since:
- 4.0.0
Example
_.differenceBy([2.1, 1.2], [2.3, 3.4], Math.floor);
// => [1.2]
// The `_.property` iteratee shorthand.
_.differenceBy([{ 'x': 2 }, { 'x': 1 }], [{ 'x': 1 }], 'x');
// => [{ 'x': 2 }]
# static differenceWith
This method is like _.difference except that it accepts comparator
which is invoked to compare elements of array to values. The order and
references of result values are determined by the first array. The comparator
is invoked with two arguments: (arrVal, othVal).
Note: Unlike _.pullAllWith, this method returns a new array.
- Since:
- 4.0.0
Example
var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
_.differenceWith(objects, [{ 'x': 1, 'y': 2 }], _.isEqual);
// => [{ 'x': 2, 'y': 1 }]
# static differenceWith
This method is like _.difference except that it accepts comparator
which is invoked to compare elements of array to values. The order and
references of result values are determined by the first array. The comparator
is invoked with two arguments: (arrVal, othVal).
Note: Unlike _.pullAllWith, this method returns a new array.
- Since:
- 4.0.0
Example
var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
_.differenceWith(objects, [{ 'x': 1, 'y': 2 }], _.isEqual);
// => [{ 'x': 2, 'y': 1 }]
# static entries
Creates an array of own enumerable string keyed-value pairs for object
which can be consumed by _.fromPairs. If object is a map or set, its
entries are returned.
- Since:
- 4.0.0
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.toPairs(new Foo);
// => [['a', 1], ['b', 2]] (iteration order is not guaranteed)
# static entries
Creates an array of own enumerable string keyed-value pairs for object
which can be consumed by _.fromPairs. If object is a map or set, its
entries are returned.
- Since:
- 4.0.0
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.toPairs(new Foo);
// => [['a', 1], ['b', 2]] (iteration order is not guaranteed)
# static entriesIn
Creates an array of own and inherited enumerable string keyed-value pairs
for object which can be consumed by _.fromPairs. If object is a map
or set, its entries are returned.
- Since:
- 4.0.0
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.toPairsIn(new Foo);
// => [['a', 1], ['b', 2], ['c', 3]] (iteration order is not guaranteed)
# static entriesIn
Creates an array of own and inherited enumerable string keyed-value pairs
for object which can be consumed by _.fromPairs. If object is a map
or set, its entries are returned.
- Since:
- 4.0.0
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.toPairsIn(new Foo);
// => [['a', 1], ['b', 2], ['c', 3]] (iteration order is not guaranteed)
# static extend
This method is like _.assign except that it iterates over own and
inherited source properties.
Note: This method mutates object.
- Since:
- 4.0.0
- See:
Example
function Foo() {
this.a = 1;
}
function Bar() {
this.c = 3;
}
Foo.prototype.b = 2;
Bar.prototype.d = 4;
_.assignIn({ 'a': 0 }, new Foo, new Bar);
// => { 'a': 1, 'b': 2, 'c': 3, 'd': 4 }
# static extend
This method is like _.assign except that it iterates over own and
inherited source properties.
Note: This method mutates object.
- Since:
- 4.0.0
- See:
Example
function Foo() {
this.a = 1;
}
function Bar() {
this.c = 3;
}
Foo.prototype.b = 2;
Bar.prototype.d = 4;
_.assignIn({ 'a': 0 }, new Foo, new Bar);
// => { 'a': 1, 'b': 2, 'c': 3, 'd': 4 }
# static extend
This method is like _.assign except that it iterates over own and
inherited source properties.
Note: This method mutates object.
- Since:
- 4.0.0
- See:
Example
function Foo() {
this.a = 1;
}
function Bar() {
this.c = 3;
}
Foo.prototype.b = 2;
Bar.prototype.d = 4;
_.assignIn({ 'a': 0 }, new Foo, new Bar);
// => { 'a': 1, 'b': 2, 'c': 3, 'd': 4 }
# static extendWith
This method is like _.assignIn except that it accepts customizer
which is invoked to produce the assigned values. If customizer returns
undefined, assignment is handled by the method instead. The customizer
is invoked with five arguments: (objValue, srcValue, key, object, source).
Note: This method mutates object.
- Since:
- 4.0.0
- See:
Example
function customizer(objValue, srcValue) {
return _.isUndefined(objValue) ? srcValue : objValue;
}
var defaults = _.partialRight(_.assignInWith, customizer);
defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
// => { 'a': 1, 'b': 2 }
# static extendWith
This method is like _.assignIn except that it accepts customizer
which is invoked to produce the assigned values. If customizer returns
undefined, assignment is handled by the method instead. The customizer
is invoked with five arguments: (objValue, srcValue, key, object, source).
Note: This method mutates object.
- Since:
- 4.0.0
- See:
Example
function customizer(objValue, srcValue) {
return _.isUndefined(objValue) ? srcValue : objValue;
}
var defaults = _.partialRight(_.assignInWith, customizer);
defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
// => { 'a': 1, 'b': 2 }
# static find
Iterates over elements of collection, returning the first element
predicate returns truthy for. The predicate is invoked with three
arguments: (value, index|key, collection).
- Since:
- 0.1.0
Example
var users = [
{ 'user': 'barney', 'age': 36, 'active': true },
{ 'user': 'fred', 'age': 40, 'active': false },
{ 'user': 'pebbles', 'age': 1, 'active': true }
];
_.find(users, function(o) { return o.age < 40; });
// => object for 'barney'
// The `_.matches` iteratee shorthand.
_.find(users, { 'age': 1, 'active': true });
// => object for 'pebbles'
// The `_.matchesProperty` iteratee shorthand.
_.find(users, ['active', false]);
// => object for 'fred'
// The `_.property` iteratee shorthand.
_.find(users, 'active');
// => object for 'barney'
# static find
Iterates over elements of collection, returning the first element
predicate returns truthy for. The predicate is invoked with three
arguments: (value, index|key, collection).
- Since:
- 0.1.0
Example
var users = [
{ 'user': 'barney', 'age': 36, 'active': true },
{ 'user': 'fred', 'age': 40, 'active': false },
{ 'user': 'pebbles', 'age': 1, 'active': true }
];
_.find(users, function(o) { return o.age < 40; });
// => object for 'barney'
// The `_.matches` iteratee shorthand.
_.find(users, { 'age': 1, 'active': true });
// => object for 'pebbles'
// The `_.matchesProperty` iteratee shorthand.
_.find(users, ['active', false]);
// => object for 'fred'
// The `_.property` iteratee shorthand.
_.find(users, 'active');
// => object for 'barney'
# static find
Iterates over elements of collection, returning the first element
predicate returns truthy for. The predicate is invoked with three
arguments: (value, index|key, collection).
- Since:
- 0.1.0
Example
var users = [
{ 'user': 'barney', 'age': 36, 'active': true },
{ 'user': 'fred', 'age': 40, 'active': false },
{ 'user': 'pebbles', 'age': 1, 'active': true }
];
_.find(users, function(o) { return o.age < 40; });
// => object for 'barney'
// The `_.matches` iteratee shorthand.
_.find(users, { 'age': 1, 'active': true });
// => object for 'pebbles'
// The `_.matchesProperty` iteratee shorthand.
_.find(users, ['active', false]);
// => object for 'fred'
// The `_.property` iteratee shorthand.
_.find(users, 'active');
// => object for 'barney'
# static findLast
This method is like _.find except that it iterates over elements of
collection from right to left.
- Since:
- 2.0.0
Example
_.findLast([1, 2, 3, 4], function(n) {
return n % 2 == 1;
});
// => 3
# static findLast
This method is like _.find except that it iterates over elements of
collection from right to left.
- Since:
- 2.0.0
Example
_.findLast([1, 2, 3, 4], function(n) {
return n % 2 == 1;
});
// => 3
# static floor
Computes number rounded down to precision.
- Since:
- 3.10.0
Example
_.floor(4.006);
// => 4
_.floor(0.046, 2);
// => 0.04
_.floor(4060, -2);
// => 4000
# static floor
Computes number rounded down to precision.
- Since:
- 3.10.0
Example
_.floor(4.006);
// => 4
_.floor(0.046, 2);
// => 0.04
_.floor(4060, -2);
// => 4000
# static flow
Creates a function that returns the result of invoking the given functions
with the this binding of the created function, where each successive
invocation is supplied the return value of the previous.
- Since:
- 3.0.0
- See:
Example
function square(n) {
return n * n;
}
var addSquare = _.flow([_.add, square]);
addSquare(1, 2);
// => 9
# static flow
Creates a function that returns the result of invoking the given functions
with the this binding of the created function, where each successive
invocation is supplied the return value of the previous.
- Since:
- 3.0.0
- See:
Example
function square(n) {
return n * n;
}
var addSquare = _.flow([_.add, square]);
addSquare(1, 2);
// => 9
# static flowRight
This method is like _.flow except that it creates a function that
invokes the given functions from right to left.
- Since:
- 3.0.0
- See:
Example
function square(n) {
return n * n;
}
var addSquare = _.flowRight([square, _.add]);
addSquare(1, 2);
// => 9
# static flowRight
This method is like _.flow except that it creates a function that
invokes the given functions from right to left.
- Since:
- 3.0.0
- See:
Example
function square(n) {
return n * n;
}
var addSquare = _.flowRight([square, _.add]);
addSquare(1, 2);
// => 9
# static groupBy
Creates an object composed of keys generated from the results of running
each element of collection thru iteratee. The order of grouped values
is determined by the order they occur in collection. The corresponding
value of each key is an array of elements responsible for generating the
key. The iteratee is invoked with one argument: (value).
- Since:
- 0.1.0
Example
_.groupBy([6.1, 4.2, 6.3], Math.floor);
// => { '4': [4.2], '6': [6.1, 6.3] }
// The `_.property` iteratee shorthand.
_.groupBy(['one', 'two', 'three'], 'length');
// => { '3': ['one', 'two'], '5': ['three'] }
# static groupBy
Creates an object composed of keys generated from the results of running
each element of collection thru iteratee. The order of grouped values
is determined by the order they occur in collection. The corresponding
value of each key is an array of elements responsible for generating the
key. The iteratee is invoked with one argument: (value).
- Since:
- 0.1.0
Example
_.groupBy([6.1, 4.2, 6.3], Math.floor);
// => { '4': [4.2], '6': [6.1, 6.3] }
// The `_.property` iteratee shorthand.
_.groupBy(['one', 'two', 'three'], 'length');
// => { '3': ['one', 'two'], '5': ['three'] }
# static gt
Checks if value is greater than other.
- Since:
- 3.9.0
- See:
Example
_.gt(3, 1);
// => true
_.gt(3, 3);
// => false
_.gt(1, 3);
// => false
# static gt
Checks if value is greater than other.
- Since:
- 3.9.0
- See:
Example
_.gt(3, 1);
// => true
_.gt(3, 3);
// => false
_.gt(1, 3);
// => false
# static gte
Checks if value is greater than or equal to other.
- Since:
- 3.9.0
- See:
Example
_.gte(3, 1);
// => true
_.gte(3, 3);
// => true
_.gte(1, 3);
// => false
# static gte
Checks if value is greater than or equal to other.
- Since:
- 3.9.0
- See:
Example
_.gte(3, 1);
// => true
_.gte(3, 3);
// => true
_.gte(1, 3);
// => false
# static intersection
Creates an array of unique values that are included in all given arrays
using SameValueZero
for equality comparisons. The order and references of result values are
determined by the first array.
- Since:
- 0.1.0
Example
_.intersection([2, 1], [2, 3]);
// => [2]
# static intersection
Creates an array of unique values that are included in all given arrays
using SameValueZero
for equality comparisons. The order and references of result values are
determined by the first array.
- Since:
- 0.1.0
Example
_.intersection([2, 1], [2, 3]);
// => [2]
# static intersectionBy
This method is like _.intersection except that it accepts iteratee
which is invoked for each element of each arrays to generate the criterion
by which they're compared. The order and references of result values are
determined by the first array. The iteratee is invoked with one argument:
(value).
- Since:
- 4.0.0
Example
_.intersectionBy([2.1, 1.2], [2.3, 3.4], Math.floor);
// => [2.1]
// The `_.property` iteratee shorthand.
_.intersectionBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x');
// => [{ 'x': 1 }]
# static intersectionBy
This method is like _.intersection except that it accepts iteratee
which is invoked for each element of each arrays to generate the criterion
by which they're compared. The order and references of result values are
determined by the first array. The iteratee is invoked with one argument:
(value).
- Since:
- 4.0.0
Example
_.intersectionBy([2.1, 1.2], [2.3, 3.4], Math.floor);
// => [2.1]
// The `_.property` iteratee shorthand.
_.intersectionBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x');
// => [{ 'x': 1 }]
# static intersectionWith
This method is like _.intersection except that it accepts comparator
which is invoked to compare elements of arrays. The order and references
of result values are determined by the first array. The comparator is
invoked with two arguments: (arrVal, othVal).
- Since:
- 4.0.0
View Source node_modules/lodash/intersectionWith.js, line 28
Example
var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }];
_.intersectionWith(objects, others, _.isEqual);
// => [{ 'x': 1, 'y': 2 }]
# static intersectionWith
This method is like _.intersection except that it accepts comparator
which is invoked to compare elements of arrays. The order and references
of result values are determined by the first array. The comparator is
invoked with two arguments: (arrVal, othVal).
- Since:
- 4.0.0
Example
var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }];
_.intersectionWith(objects, others, _.isEqual);
// => [{ 'x': 1, 'y': 2 }]
# static invert
Creates an object composed of the inverted keys and values of object.
If object contains duplicate values, subsequent values overwrite
property assignments of previous values.
- Since:
- 0.7.0
Example
var object = { 'a': 1, 'b': 2, 'c': 1 };
_.invert(object);
// => { '1': 'c', '2': 'b' }
# static invert
Creates an object composed of the inverted keys and values of object.
If object contains duplicate values, subsequent values overwrite
property assignments of previous values.
- Since:
- 0.7.0
Example
var object = { 'a': 1, 'b': 2, 'c': 1 };
_.invert(object);
// => { '1': 'c', '2': 'b' }
# static invertBy
This method is like _.invert except that the inverted object is generated
from the results of running each element of object thru iteratee. The
corresponding inverted value of each inverted key is an array of keys
responsible for generating the inverted value. The iteratee is invoked
with one argument: (value).
- Since:
- 4.1.0
Example
var object = { 'a': 1, 'b': 2, 'c': 1 };
_.invertBy(object);
// => { '1': ['a', 'c'], '2': ['b'] }
_.invertBy(object, function(value) {
return 'group' + value;
});
// => { 'group1': ['a', 'c'], 'group2': ['b'] }
# static invertBy
This method is like _.invert except that the inverted object is generated
from the results of running each element of object thru iteratee. The
corresponding inverted value of each inverted key is an array of keys
responsible for generating the inverted value. The iteratee is invoked
with one argument: (value).
- Since:
- 4.1.0
Example
var object = { 'a': 1, 'b': 2, 'c': 1 };
_.invertBy(object);
// => { '1': ['a', 'c'], '2': ['b'] }
_.invertBy(object, function(value) {
return 'group' + value;
});
// => { 'group1': ['a', 'c'], 'group2': ['b'] }
# static invoke
Invokes the method at path of object.
- Since:
- 4.0.0
Example
var object = { 'a': [{ 'b': { 'c': [1, 2, 3, 4] } }] };
_.invoke(object, 'a[0].b.c.slice', 1, 3);
// => [2, 3]
# static invoke
Invokes the method at path of object.
- Since:
- 4.0.0
Example
var object = { 'a': [{ 'b': { 'c': [1, 2, 3, 4] } }] };
_.invoke(object, 'a[0].b.c.slice', 1, 3);
// => [2, 3]
# static invokeMap
Invokes the method at path of each element in collection, returning
an array of the results of each invoked method. Any additional arguments
are provided to each invoked method. If path is a function, it's invoked
for, and this bound to, each element in collection.
- Since:
- 4.0.0
Example
_.invokeMap([[5, 1, 7], [3, 2, 1]], 'sort');
// => [[1, 5, 7], [1, 2, 3]]
_.invokeMap([123, 456], String.prototype.split, '');
// => [['1', '2', '3'], ['4', '5', '6']]
# static invokeMap
Invokes the method at path of each element in collection, returning
an array of the results of each invoked method. Any additional arguments
are provided to each invoked method. If path is a function, it's invoked
for, and this bound to, each element in collection.
- Since:
- 4.0.0
Example
_.invokeMap([[5, 1, 7], [3, 2, 1]], 'sort');
// => [[1, 5, 7], [1, 2, 3]]
_.invokeMap([123, 456], String.prototype.split, '');
// => [['1', '2', '3'], ['4', '5', '6']]
# static isArguments
Checks if value is likely an arguments object.
- Since:
- 0.1.0
Example
_.isArguments(function() { return arguments; }());
// => true
_.isArguments([1, 2, 3]);
// => false
# static isArguments
Checks if value is likely an arguments object.
- Since:
- 0.1.0
Example
_.isArguments(function() { return arguments; }());
// => true
_.isArguments([1, 2, 3]);
// => false
# static isArguments
Checks if value is likely an arguments object.
- Since:
- 0.1.0
Example
_.isArguments(function() { return arguments; }());
// => true
_.isArguments([1, 2, 3]);
// => false
# static isArray
Checks if value is classified as an Array object.
- Since:
- 0.1.0
Example
_.isArray([1, 2, 3]);
// => true
_.isArray(document.body.children);
// => false
_.isArray('abc');
// => false
_.isArray(_.noop);
// => false
# static isArray
Checks if value is classified as an Array object.
- Since:
- 0.1.0
Example
_.isArray([1, 2, 3]);
// => true
_.isArray(document.body.children);
// => false
_.isArray('abc');
// => false
_.isArray(_.noop);
// => false
# static isArray
Checks if value is classified as an Array object.
- Since:
- 0.1.0
Example
_.isArray([1, 2, 3]);
// => true
_.isArray(document.body.children);
// => false
_.isArray('abc');
// => false
_.isArray(_.noop);
// => false
# static isArrayBuffer
Checks if value is classified as an ArrayBuffer object.
- Since:
- 4.3.0
Example
_.isArrayBuffer(new ArrayBuffer(2));
// => true
_.isArrayBuffer(new Array(2));
// => false
# static isArrayBuffer
Checks if value is classified as an ArrayBuffer object.
- Since:
- 4.3.0
Example
_.isArrayBuffer(new ArrayBuffer(2));
// => true
_.isArrayBuffer(new Array(2));
// => false
# static isBuffer
Checks if value is a buffer.
- Since:
- 4.3.0
Example
_.isBuffer(new Buffer(2));
// => true
_.isBuffer(new Uint8Array(2));
// => false
# static isBuffer
Checks if value is a buffer.
- Since:
- 4.3.0
Example
_.isBuffer(new Buffer(2));
// => true
_.isBuffer(new Uint8Array(2));
// => false
# static isDate
Checks if value is classified as a Date object.
- Since:
- 0.1.0
Example
_.isDate(new Date);
// => true
_.isDate('Mon April 23 2012');
// => false
# static isDate
Checks if value is classified as a Date object.
- Since:
- 0.1.0
Example
_.isDate(new Date);
// => true
_.isDate('Mon April 23 2012');
// => false
# static isDate
Checks if value is classified as a Date object.
- Since:
- 0.1.0
Example
_.isDate(new Date);
// => true
_.isDate('Mon April 23 2012');
// => false
# static isMap
Checks if value is classified as a Map object.
- Since:
- 4.3.0
Example
_.isMap(new Map);
// => true
_.isMap(new WeakMap);
// => false
# static isMap
Checks if value is classified as a Map object.
- Since:
- 4.3.0
Example
_.isMap(new Map);
// => true
_.isMap(new WeakMap);
// => false
# static isRegExp
Checks if value is classified as a RegExp object.
- Since:
- 0.1.0
Example
_.isRegExp(/abc/);
// => true
_.isRegExp('/abc/');
// => false
# static isRegExp
Checks if value is classified as a RegExp object.
- Since:
- 0.1.0
Example
_.isRegExp(/abc/);
// => true
_.isRegExp('/abc/');
// => false
# static isRegExp
Checks if value is classified as a RegExp object.
- Since:
- 0.1.0
Example
_.isRegExp(/abc/);
// => true
_.isRegExp('/abc/');
// => false
# static isSet
Checks if value is classified as a Set object.
- Since:
- 4.3.0
Example
_.isSet(new Set);
// => true
_.isSet(new WeakSet);
// => false
# static isSet
Checks if value is classified as a Set object.
- Since:
- 4.3.0
Example
_.isSet(new Set);
// => true
_.isSet(new WeakSet);
// => false
# static isTypedArray
Checks if value is classified as a typed array.
- Since:
- 3.0.0
Example
_.isTypedArray(new Uint8Array);
// => true
_.isTypedArray([]);
// => false
# static isTypedArray
Checks if value is classified as a typed array.
- Since:
- 3.0.0
Example
_.isTypedArray(new Uint8Array);
// => true
_.isTypedArray([]);
// => false
# static iteratee
Creates a function that invokes func with the arguments of the created
function. If func is a property name, the created function returns the
property value for a given element. If func is an array or object, the
created function returns true for elements that contain the equivalent
source properties, otherwise it returns false.
- Since:
- 4.0.0
Example
var users = [
{ 'user': 'barney', 'age': 36, 'active': true },
{ 'user': 'fred', 'age': 40, 'active': false }
];
// The `_.matches` iteratee shorthand.
_.filter(users, _.iteratee({ 'user': 'barney', 'active': true }));
// => [{ 'user': 'barney', 'age': 36, 'active': true }]
// The `_.matchesProperty` iteratee shorthand.
_.filter(users, _.iteratee(['user', 'fred']));
// => [{ 'user': 'fred', 'age': 40 }]
// The `_.property` iteratee shorthand.
_.map(users, _.iteratee('user'));
// => ['barney', 'fred']
// Create custom iteratee shorthands.
_.iteratee = _.wrap(_.iteratee, function(iteratee, func) {
return !_.isRegExp(func) ? iteratee(func) : function(string) {
return func.test(string);
};
});
_.filter(['abc', 'def'], /ef/);
// => ['def']
# static kebabCase
Converts string to
kebab case.
- Since:
- 3.0.0
Example
_.kebabCase('Foo Bar');
// => 'foo-bar'
_.kebabCase('fooBar');
// => 'foo-bar'
_.kebabCase('__FOO_BAR__');
// => 'foo-bar'
# static kebabCase
Converts string to
kebab case.
- Since:
- 3.0.0
Example
_.kebabCase('Foo Bar');
// => 'foo-bar'
_.kebabCase('fooBar');
// => 'foo-bar'
_.kebabCase('__FOO_BAR__');
// => 'foo-bar'
# static keyBy
Creates an object composed of keys generated from the results of running
each element of collection thru iteratee. The corresponding value of
each key is the last element responsible for generating the key. The
iteratee is invoked with one argument: (value).
- Since:
- 4.0.0
Example
var array = [
{ 'dir': 'left', 'code': 97 },
{ 'dir': 'right', 'code': 100 }
];
_.keyBy(array, function(o) {
return String.fromCharCode(o.code);
});
// => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } }
_.keyBy(array, 'dir');
// => { 'left': { 'dir': 'left', 'code': 97 }, 'right': { 'dir': 'right', 'code': 100 } }
# static keyBy
Creates an object composed of keys generated from the results of running
each element of collection thru iteratee. The corresponding value of
each key is the last element responsible for generating the key. The
iteratee is invoked with one argument: (value).
- Since:
- 4.0.0
Example
var array = [
{ 'dir': 'left', 'code': 97 },
{ 'dir': 'right', 'code': 100 }
];
_.keyBy(array, function(o) {
return String.fromCharCode(o.code);
});
// => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } }
_.keyBy(array, 'dir');
// => { 'left': { 'dir': 'left', 'code': 97 }, 'right': { 'dir': 'right', 'code': 100 } }
# static keys
Creates an array of the own enumerable property names of object.
Note: Non-object values are coerced to objects. See the ES spec for more details.
- Since:
- 0.1.0
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.keys(new Foo);
// => ['a', 'b'] (iteration order is not guaranteed)
_.keys('hi');
// => ['0', '1']
# static keysIn
Creates an array of the own and inherited enumerable property names of object.
Note: Non-object values are coerced to objects.
- Since:
- 3.0.0
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.keysIn(new Foo);
// => ['a', 'b', 'c'] (iteration order is not guaranteed)
# static lowerCase
Converts string, as space separated words, to lower case.
- Since:
- 4.0.0
Example
_.lowerCase('--Foo-Bar--');
// => 'foo bar'
_.lowerCase('fooBar');
// => 'foo bar'
_.lowerCase('__FOO_BAR__');
// => 'foo bar'
# static lowerCase
Converts string, as space separated words, to lower case.
- Since:
- 4.0.0
Example
_.lowerCase('--Foo-Bar--');
// => 'foo bar'
_.lowerCase('fooBar');
// => 'foo bar'
_.lowerCase('__FOO_BAR__');
// => 'foo bar'
# static lowerFirst
Converts the first character of string to lower case.
- Since:
- 4.0.0
Example
_.lowerFirst('Fred');
// => 'fred'
_.lowerFirst('FRED');
// => 'fRED'
# static lowerFirst
Converts the first character of string to lower case.
- Since:
- 4.0.0
Example
_.lowerFirst('Fred');
// => 'fred'
_.lowerFirst('FRED');
// => 'fRED'
# static lt
Checks if value is less than other.
- Since:
- 3.9.0
- See:
Example
_.lt(1, 3);
// => true
_.lt(3, 3);
// => false
_.lt(3, 1);
// => false
# static lt
Checks if value is less than other.
- Since:
- 3.9.0
- See:
Example
_.lt(1, 3);
// => true
_.lt(3, 3);
// => false
_.lt(3, 1);
// => false
# static lte
Checks if value is less than or equal to other.
- Since:
- 3.9.0
- See:
Example
_.lte(1, 3);
// => true
_.lte(3, 3);
// => true
_.lte(3, 1);
// => false
# static lte
Checks if value is less than or equal to other.
- Since:
- 3.9.0
- See:
Example
_.lte(1, 3);
// => true
_.lte(3, 3);
// => true
_.lte(3, 1);
// => false
# static merge
This method is like _.assign except that it recursively merges own and
inherited enumerable string keyed properties of source objects into the
destination object. Source properties that resolve to undefined are
skipped if a destination value exists. Array and plain object properties
are merged recursively. Other objects and value types are overridden by
assignment. Source objects are applied from left to right. Subsequent
sources overwrite property assignments of previous sources.
Note: This method mutates object.
- Since:
- 0.5.0
Example
var object = {
'a': [{ 'b': 2 }, { 'd': 4 }]
};
var other = {
'a': [{ 'c': 3 }, { 'e': 5 }]
};
_.merge(object, other);
// => { 'a': [{ 'b': 2, 'c': 3 }, { 'd': 4, 'e': 5 }] }
# static merge
This method is like _.assign except that it recursively merges own and
inherited enumerable string keyed properties of source objects into the
destination object. Source properties that resolve to undefined are
skipped if a destination value exists. Array and plain object properties
are merged recursively. Other objects and value types are overridden by
assignment. Source objects are applied from left to right. Subsequent
sources overwrite property assignments of previous sources.
Note: This method mutates object.
- Since:
- 0.5.0
Example
var object = {
'a': [{ 'b': 2 }, { 'd': 4 }]
};
var other = {
'a': [{ 'c': 3 }, { 'e': 5 }]
};
_.merge(object, other);
// => { 'a': [{ 'b': 2, 'c': 3 }, { 'd': 4, 'e': 5 }] }
# static mergeWith
This method is like _.merge except that it accepts customizer which
is invoked to produce the merged values of the destination and source
properties. If customizer returns undefined, merging is handled by the
method instead. The customizer is invoked with six arguments:
(objValue, srcValue, key, object, source, stack).
Note: This method mutates object.
- Since:
- 4.0.0
Example
function customizer(objValue, srcValue) {
if (_.isArray(objValue)) {
return objValue.concat(srcValue);
}
}
var object = { 'a': [1], 'b': [2] };
var other = { 'a': [3], 'b': [4] };
_.mergeWith(object, other, customizer);
// => { 'a': [1, 3], 'b': [2, 4] }
# static mergeWith
This method is like _.merge except that it accepts customizer which
is invoked to produce the merged values of the destination and source
properties. If customizer returns undefined, merging is handled by the
method instead. The customizer is invoked with six arguments:
(objValue, srcValue, key, object, source, stack).
Note: This method mutates object.
- Since:
- 4.0.0
Example
function customizer(objValue, srcValue) {
if (_.isArray(objValue)) {
return objValue.concat(srcValue);
}
}
var object = { 'a': [1], 'b': [2] };
var other = { 'a': [3], 'b': [4] };
_.mergeWith(object, other, customizer);
// => { 'a': [1, 3], 'b': [2, 4] }
# static method
Creates a function that invokes the method at path of a given object.
Any additional arguments are provided to the invoked method.
- Since:
- 3.7.0
Example
var objects = [
{ 'a': { 'b': _.constant(2) } },
{ 'a': { 'b': _.constant(1) } }
];
_.map(objects, _.method('a.b'));
// => [2, 1]
_.map(objects, _.method(['a', 'b']));
// => [2, 1]
# static method
Creates a function that invokes the method at path of a given object.
Any additional arguments are provided to the invoked method.
- Since:
- 3.7.0
Example
var objects = [
{ 'a': { 'b': _.constant(2) } },
{ 'a': { 'b': _.constant(1) } }
];
_.map(objects, _.method('a.b'));
// => [2, 1]
_.map(objects, _.method(['a', 'b']));
// => [2, 1]
# static methodOf
The opposite of _.method; this method creates a function that invokes
the method at a given path of object. Any additional arguments are
provided to the invoked method.
- Since:
- 3.7.0
Example
var array = _.times(3, _.constant),
object = { 'a': array, 'b': array, 'c': array };
_.map(['a[2]', 'c[0]'], _.methodOf(object));
// => [2, 0]
_.map([['a', '2'], ['c', '0']], _.methodOf(object));
// => [2, 0]
# static methodOf
The opposite of _.method; this method creates a function that invokes
the method at a given path of object. Any additional arguments are
provided to the invoked method.
- Since:
- 3.7.0
Example
var array = _.times(3, _.constant),
object = { 'a': array, 'b': array, 'c': array };
_.map(['a[2]', 'c[0]'], _.methodOf(object));
// => [2, 0]
_.map([['a', '2'], ['c', '0']], _.methodOf(object));
// => [2, 0]
# static next
Gets the next value on a wrapped object following the iterator protocol.
- Since:
- 4.0.0
Example
var wrapped = _([1, 2]);
wrapped.next();
// => { 'done': false, 'value': 1 }
wrapped.next();
// => { 'done': false, 'value': 2 }
wrapped.next();
// => { 'done': true, 'value': undefined }
# static next
Gets the next value on a wrapped object following the iterator protocol.
- Since:
- 4.0.0
Example
var wrapped = _([1, 2]);
wrapped.next();
// => { 'done': false, 'value': 1 }
wrapped.next();
// => { 'done': false, 'value': 2 }
wrapped.next();
// => { 'done': true, 'value': undefined }
# static now
Gets the timestamp of the number of milliseconds that have elapsed since the Unix epoch (1 January 1970 00:00:00 UTC).
- Since:
- 2.4.0
Example
_.defer(function(stamp) {
console.log(_.now() - stamp);
}, _.now());
// => Logs the number of milliseconds it took for the deferred invocation.
# static omit
The opposite of _.pick; this method creates an object composed of the
own and inherited enumerable property paths of object that are not omitted.
Note: This method is considerably slower than _.pick.
- Since:
- 0.1.0
Example
var object = { 'a': 1, 'b': '2', 'c': 3 };
_.omit(object, ['a', 'c']);
// => { 'b': '2' }
# static omit
The opposite of _.pick; this method creates an object composed of the
own and inherited enumerable property paths of object that are not omitted.
Note: This method is considerably slower than _.pick.
- Since:
- 0.1.0
Example
var object = { 'a': 1, 'b': '2', 'c': 3 };
_.omit(object, ['a', 'c']);
// => { 'b': '2' }
# static over
Creates a function that invokes iteratees with the arguments it receives
and returns their results.
- Since:
- 4.0.0
Example
var func = _.over([Math.max, Math.min]);
func(1, 2, 3, 4);
// => [4, 1]
# static over
Creates a function that invokes iteratees with the arguments it receives
and returns their results.
- Since:
- 4.0.0
Example
var func = _.over([Math.max, Math.min]);
func(1, 2, 3, 4);
// => [4, 1]
# static overArgs
Creates a function that invokes func with its arguments transformed.
- Since:
- 4.0.0
Example
function doubled(n) {
return n * 2;
}
function square(n) {
return n * n;
}
var func = _.overArgs(function(x, y) {
return [x, y];
}, [square, doubled]);
func(9, 3);
// => [81, 6]
func(10, 5);
// => [100, 10]
# static overArgs
Creates a function that invokes func with its arguments transformed.
- Since:
- 4.0.0
Example
function doubled(n) {
return n * 2;
}
function square(n) {
return n * n;
}
var func = _.overArgs(function(x, y) {
return [x, y];
}, [square, doubled]);
func(9, 3);
// => [81, 6]
func(10, 5);
// => [100, 10]
# static overEvery
Creates a function that checks if all of the predicates return
truthy when invoked with the arguments it receives.
Following shorthands are possible for providing predicates.
Pass an Object and it will be used as an parameter for _.matches to create the predicate.
Pass an Array of parameters for _.matchesProperty and the predicate will be created using them.
- Since:
- 4.0.0
Example
var func = _.overEvery([Boolean, isFinite]);
func('1');
// => true
func(null);
// => false
func(NaN);
// => false
# static overEvery
Creates a function that checks if all of the predicates return
truthy when invoked with the arguments it receives.
Following shorthands are possible for providing predicates.
Pass an Object and it will be used as an parameter for _.matches to create the predicate.
Pass an Array of parameters for _.matchesProperty and the predicate will be created using them.
- Since:
- 4.0.0
Example
var func = _.overEvery([Boolean, isFinite]);
func('1');
// => true
func(null);
// => false
func(NaN);
// => false
# static overSome
Creates a function that checks if any of the predicates return
truthy when invoked with the arguments it receives.
Following shorthands are possible for providing predicates.
Pass an Object and it will be used as an parameter for _.matches to create the predicate.
Pass an Array of parameters for _.matchesProperty and the predicate will be created using them.
- Since:
- 4.0.0
Example
var func = _.overSome([Boolean, isFinite]);
func('1');
// => true
func(null);
// => true
func(NaN);
// => false
var matchesFunc = _.overSome([{ 'a': 1 }, { 'a': 2 }])
var matchesPropertyFunc = _.overSome([['a', 1], ['a', 2]])
# static overSome
Creates a function that checks if any of the predicates return
truthy when invoked with the arguments it receives.
Following shorthands are possible for providing predicates.
Pass an Object and it will be used as an parameter for _.matches to create the predicate.
Pass an Array of parameters for _.matchesProperty and the predicate will be created using them.
- Since:
- 4.0.0
Example
var func = _.overSome([Boolean, isFinite]);
func('1');
// => true
func(null);
// => true
func(NaN);
// => false
var matchesFunc = _.overSome([{ 'a': 1 }, { 'a': 2 }])
var matchesPropertyFunc = _.overSome([['a', 1], ['a', 2]])
# static partial
Creates a function that invokes func with partials prepended to the
arguments it receives. This method is like _.bind except it does not
alter the this binding.
The _.partial.placeholder value, which defaults to _ in monolithic
builds, may be used as a placeholder for partially applied arguments.
Note: This method doesn't set the "length" property of partially applied functions.
- Since:
- 0.2.0
Example
function greet(greeting, name) {
return greeting + ' ' + name;
}
var sayHelloTo = _.partial(greet, 'hello');
sayHelloTo('fred');
// => 'hello fred'
// Partially applied with placeholders.
var greetFred = _.partial(greet, _, 'fred');
greetFred('hi');
// => 'hi fred'
# static partial
Creates a function that invokes func with partials prepended to the
arguments it receives. This method is like _.bind except it does not
alter the this binding.
The _.partial.placeholder value, which defaults to _ in monolithic
builds, may be used as a placeholder for partially applied arguments.
Note: This method doesn't set the "length" property of partially applied functions.
- Since:
- 0.2.0
Example
function greet(greeting, name) {
return greeting + ' ' + name;
}
var sayHelloTo = _.partial(greet, 'hello');
sayHelloTo('fred');
// => 'hello fred'
// Partially applied with placeholders.
var greetFred = _.partial(greet, _, 'fred');
greetFred('hi');
// => 'hi fred'
# static partialRight
This method is like _.partial except that partially applied arguments
are appended to the arguments it receives.
The _.partialRight.placeholder value, which defaults to _ in monolithic
builds, may be used as a placeholder for partially applied arguments.
Note: This method doesn't set the "length" property of partially applied functions.
- Since:
- 1.0.0
Example
function greet(greeting, name) {
return greeting + ' ' + name;
}
var greetFred = _.partialRight(greet, 'fred');
greetFred('hi');
// => 'hi fred'
// Partially applied with placeholders.
var sayHelloTo = _.partialRight(greet, 'hello', _);
sayHelloTo('fred');
// => 'hello fred'
# static partialRight
This method is like _.partial except that partially applied arguments
are appended to the arguments it receives.
The _.partialRight.placeholder value, which defaults to _ in monolithic
builds, may be used as a placeholder for partially applied arguments.
Note: This method doesn't set the "length" property of partially applied functions.
- Since:
- 1.0.0
Example
function greet(greeting, name) {
return greeting + ' ' + name;
}
var greetFred = _.partialRight(greet, 'fred');
greetFred('hi');
// => 'hi fred'
// Partially applied with placeholders.
var sayHelloTo = _.partialRight(greet, 'hello', _);
sayHelloTo('fred');
// => 'hello fred'
# static partition
Creates an array of elements split into two groups, the first of which
contains elements predicate returns truthy for, the second of which
contains elements predicate returns falsey for. The predicate is
invoked with one argument: (value).
- Since:
- 3.0.0
Example
var users = [
{ 'user': 'barney', 'age': 36, 'active': false },
{ 'user': 'fred', 'age': 40, 'active': true },
{ 'user': 'pebbles', 'age': 1, 'active': false }
];
_.partition(users, function(o) { return o.active; });
// => objects for [['fred'], ['barney', 'pebbles']]
// The `_.matches` iteratee shorthand.
_.partition(users, { 'age': 1, 'active': false });
// => objects for [['pebbles'], ['barney', 'fred']]
// The `_.matchesProperty` iteratee shorthand.
_.partition(users, ['active', false]);
// => objects for [['barney', 'pebbles'], ['fred']]
// The `_.property` iteratee shorthand.
_.partition(users, 'active');
// => objects for [['fred'], ['barney', 'pebbles']]
# static partition
Creates an array of elements split into two groups, the first of which
contains elements predicate returns truthy for, the second of which
contains elements predicate returns falsey for. The predicate is
invoked with one argument: (value).
- Since:
- 3.0.0
Example
var users = [
{ 'user': 'barney', 'age': 36, 'active': false },
{ 'user': 'fred', 'age': 40, 'active': true },
{ 'user': 'pebbles', 'age': 1, 'active': false }
];
_.partition(users, function(o) { return o.active; });
// => objects for [['fred'], ['barney', 'pebbles']]
// The `_.matches` iteratee shorthand.
_.partition(users, { 'age': 1, 'active': false });
// => objects for [['pebbles'], ['barney', 'fred']]
// The `_.matchesProperty` iteratee shorthand.
_.partition(users, ['active', false]);
// => objects for [['barney', 'pebbles'], ['fred']]
// The `_.property` iteratee shorthand.
_.partition(users, 'active');
// => objects for [['fred'], ['barney', 'pebbles']]
# static pick
Creates an object composed of the picked object properties.
- Since:
- 0.1.0
Example
var object = { 'a': 1, 'b': '2', 'c': 3 };
_.pick(object, ['a', 'c']);
// => { 'a': 1, 'c': 3 }
# static pick
Creates an object composed of the picked object properties.
- Since:
- 0.1.0
Example
var object = { 'a': 1, 'b': '2', 'c': 3 };
_.pick(object, ['a', 'c']);
// => { 'a': 1, 'c': 3 }
# static pick
Creates an object composed of the picked object properties.
- Since:
- 0.1.0
Example
var object = { 'a': 1, 'b': '2', 'c': 3 };
_.pick(object, ['a', 'c']);
// => { 'a': 1, 'c': 3 }
# static plant
Creates a clone of the chain sequence planting value as the wrapped value.
- Since:
- 3.2.0
Example
function square(n) {
return n * n;
}
var wrapped = _([1, 2]).map(square);
var other = wrapped.plant([3, 4]);
other.value();
// => [9, 16]
wrapped.value();
// => [1, 4]
# static plant
Creates a clone of the chain sequence planting value as the wrapped value.
- Since:
- 3.2.0
Example
function square(n) {
return n * n;
}
var wrapped = _([1, 2]).map(square);
var other = wrapped.plant([3, 4]);
other.value();
// => [9, 16]
wrapped.value();
// => [1, 4]
# static pull
Removes all given values from array using
SameValueZero
for equality comparisons.
Note: Unlike _.without, this method mutates array. Use _.remove
to remove elements from an array by predicate.
- Since:
- 2.0.0
Example
var array = ['a', 'b', 'c', 'a', 'b', 'c'];
_.pull(array, 'a', 'c');
console.log(array);
// => ['b', 'b']
# static pull
Removes all given values from array using
SameValueZero
for equality comparisons.
Note: Unlike _.without, this method mutates array. Use _.remove
to remove elements from an array by predicate.
- Since:
- 2.0.0
Example
var array = ['a', 'b', 'c', 'a', 'b', 'c'];
_.pull(array, 'a', 'c');
console.log(array);
// => ['b', 'b']
# static pullAt
Removes elements from array corresponding to indexes and returns an
array of removed elements.
Note: Unlike _.at, this method mutates array.
- Since:
- 3.0.0
Example
var array = ['a', 'b', 'c', 'd'];
var pulled = _.pullAt(array, [1, 3]);
console.log(array);
// => ['a', 'c']
console.log(pulled);
// => ['b', 'd']
# static pullAt
Removes elements from array corresponding to indexes and returns an
array of removed elements.
Note: Unlike _.at, this method mutates array.
- Since:
- 3.0.0
Example
var array = ['a', 'b', 'c', 'd'];
var pulled = _.pullAt(array, [1, 3]);
console.log(array);
// => ['a', 'c']
console.log(pulled);
// => ['b', 'd']
# static range
Creates an array of numbers (positive and/or negative) progressing from
start up to, but not including, end. A step of -1 is used if a negative
start is specified without an end or step. If end is not specified,
it's set to start with start then set to 0.
Note: JavaScript follows the IEEE-754 standard for resolving floating-point values which can produce unexpected results.
- Since:
- 0.1.0
- See:
-
- _.inRange, _.rangeRight
Example
_.range(4);
// => [0, 1, 2, 3]
_.range(-4);
// => [0, -1, -2, -3]
_.range(1, 5);
// => [1, 2, 3, 4]
_.range(0, 20, 5);
// => [0, 5, 10, 15]
_.range(0, -4, -1);
// => [0, -1, -2, -3]
_.range(1, 4, 0);
// => [1, 1, 1]
_.range(0);
// => []
# static range
Creates an array of numbers (positive and/or negative) progressing from
start up to, but not including, end. A step of -1 is used if a negative
start is specified without an end or step. If end is not specified,
it's set to start with start then set to 0.
Note: JavaScript follows the IEEE-754 standard for resolving floating-point values which can produce unexpected results.
- Since:
- 0.1.0
- See:
-
- _.inRange, _.rangeRight
Example
_.range(4);
// => [0, 1, 2, 3]
_.range(-4);
// => [0, -1, -2, -3]
_.range(1, 5);
// => [1, 2, 3, 4]
_.range(0, 20, 5);
// => [0, 5, 10, 15]
_.range(0, -4, -1);
// => [0, -1, -2, -3]
_.range(1, 4, 0);
// => [1, 1, 1]
_.range(0);
// => []
# static rangeRight
This method is like _.range except that it populates values in
descending order.
- Since:
- 4.0.0
- See:
-
- _.inRange, _.range
Example
_.rangeRight(4);
// => [3, 2, 1, 0]
_.rangeRight(-4);
// => [-3, -2, -1, 0]
_.rangeRight(1, 5);
// => [4, 3, 2, 1]
_.rangeRight(0, 20, 5);
// => [15, 10, 5, 0]
_.rangeRight(0, -4, -1);
// => [-3, -2, -1, 0]
_.rangeRight(1, 4, 0);
// => [1, 1, 1]
_.rangeRight(0);
// => []
# static rangeRight
This method is like _.range except that it populates values in
descending order.
- Since:
- 4.0.0
- See:
-
- _.inRange, _.range
Example
_.rangeRight(4);
// => [3, 2, 1, 0]
_.rangeRight(-4);
// => [-3, -2, -1, 0]
_.rangeRight(1, 5);
// => [4, 3, 2, 1]
_.rangeRight(0, 20, 5);
// => [15, 10, 5, 0]
_.rangeRight(0, -4, -1);
// => [-3, -2, -1, 0]
_.rangeRight(1, 4, 0);
// => [1, 1, 1]
_.rangeRight(0);
// => []
# static rearg
Creates a function that invokes func with arguments arranged according
to the specified indexes where the argument value at the first index is
provided as the first argument, the argument value at the second index is
provided as the second argument, and so on.
- Since:
- 3.0.0
Example
var rearged = _.rearg(function(a, b, c) {
return [a, b, c];
}, [2, 0, 1]);
rearged('b', 'c', 'a')
// => ['a', 'b', 'c']
# static rearg
Creates a function that invokes func with arguments arranged according
to the specified indexes where the argument value at the first index is
provided as the first argument, the argument value at the second index is
provided as the second argument, and so on.
- Since:
- 3.0.0
Example
var rearged = _.rearg(function(a, b, c) {
return [a, b, c];
}, [2, 0, 1]);
rearged('b', 'c', 'a')
// => ['a', 'b', 'c']
# static reverse
This method is the wrapper version of _.reverse.
Note: This method mutates the wrapped array.
- Since:
- 0.1.0
Example
var array = [1, 2, 3];
_(array).reverse().value()
// => [3, 2, 1]
console.log(array);
// => [3, 2, 1]
# static reverse
This method is the wrapper version of _.reverse.
Note: This method mutates the wrapped array.
- Since:
- 0.1.0
Example
var array = [1, 2, 3];
_(array).reverse().value()
// => [3, 2, 1]
console.log(array);
// => [3, 2, 1]
# static round
Computes number rounded to precision.
- Since:
- 3.10.0
Example
_.round(4.006);
// => 4
_.round(4.006, 2);
// => 4.01
_.round(4060, -2);
// => 4100
# static round
Computes number rounded to precision.
- Since:
- 3.10.0
Example
_.round(4.006);
// => 4
_.round(4.006, 2);
// => 4.01
_.round(4060, -2);
// => 4100
# static snakeCase
Converts string to
snake case.
- Since:
- 3.0.0
Example
_.snakeCase('Foo Bar');
// => 'foo_bar'
_.snakeCase('fooBar');
// => 'foo_bar'
_.snakeCase('--FOO-BAR--');
// => 'foo_bar'
# static snakeCase
Converts string to
snake case.
- Since:
- 3.0.0
Example
_.snakeCase('Foo Bar');
// => 'foo_bar'
_.snakeCase('fooBar');
// => 'foo_bar'
_.snakeCase('--FOO-BAR--');
// => 'foo_bar'
# static sortBy
Creates an array of elements, sorted in ascending order by the results of running each element in a collection thru each iteratee. This method performs a stable sort, that is, it preserves the original sort order of equal elements. The iteratees are invoked with one argument: (value).
- Since:
- 0.1.0
Example
var users = [
{ 'user': 'fred', 'age': 48 },
{ 'user': 'barney', 'age': 36 },
{ 'user': 'fred', 'age': 30 },
{ 'user': 'barney', 'age': 34 }
];
_.sortBy(users, [function(o) { return o.user; }]);
// => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 30]]
_.sortBy(users, ['user', 'age']);
// => objects for [['barney', 34], ['barney', 36], ['fred', 30], ['fred', 48]]
# static sortBy
Creates an array of elements, sorted in ascending order by the results of running each element in a collection thru each iteratee. This method performs a stable sort, that is, it preserves the original sort order of equal elements. The iteratees are invoked with one argument: (value).
- Since:
- 0.1.0
Example
var users = [
{ 'user': 'fred', 'age': 48 },
{ 'user': 'barney', 'age': 36 },
{ 'user': 'fred', 'age': 30 },
{ 'user': 'barney', 'age': 34 }
];
_.sortBy(users, [function(o) { return o.user; }]);
// => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 30]]
_.sortBy(users, ['user', 'age']);
// => objects for [['barney', 34], ['barney', 36], ['fred', 30], ['fred', 48]]
# static startCase
Converts string to
start case.
- Since:
- 3.1.0
Example
_.startCase('--foo-bar--');
// => 'Foo Bar'
_.startCase('fooBar');
// => 'Foo Bar'
_.startCase('__FOO_BAR__');
// => 'FOO BAR'
# static startCase
Converts string to
start case.
- Since:
- 3.1.0
Example
_.startCase('--foo-bar--');
// => 'Foo Bar'
_.startCase('fooBar');
// => 'Foo Bar'
_.startCase('__FOO_BAR__');
// => 'FOO BAR'
# static templateSettings
By default, the template delimiters used by lodash are like those in embedded Ruby (ERB) as well as ES2015 template strings. Change the following template settings to use alternative delimiters.
# static toInteger
Converts value to an integer.
Note: This method is loosely based on
ToInteger.
- Since:
- 4.0.0
Example
_.toInteger(3.2);
// => 3
_.toInteger(Number.MIN_VALUE);
// => 0
_.toInteger(Infinity);
// => 1.7976931348623157e+308
_.toInteger('3.2');
// => 3
# static toNumber
Converts value to a number.
- Since:
- 4.0.0
Example
_.toNumber(3.2);
// => 3.2
_.toNumber(Number.MIN_VALUE);
// => 5e-324
_.toNumber(Infinity);
// => Infinity
_.toNumber('3.2');
// => 3.2
# static union
Creates an array of unique values, in order, from all given arrays using
SameValueZero
for equality comparisons.
- Since:
- 0.1.0
Example
_.union([2], [1, 2]);
// => [2, 1]
# static union
Creates an array of unique values, in order, from all given arrays using
SameValueZero
for equality comparisons.
- Since:
- 0.1.0
Example
_.union([2], [1, 2]);
// => [2, 1]
# static unionBy
This method is like _.union except that it accepts iteratee which is
invoked for each element of each arrays to generate the criterion by
which uniqueness is computed. Result values are chosen from the first
array in which the value occurs. The iteratee is invoked with one argument:
(value).
- Since:
- 4.0.0
Example
_.unionBy([2.1], [1.2, 2.3], Math.floor);
// => [2.1, 1.2]
// The `_.property` iteratee shorthand.
_.unionBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x');
// => [{ 'x': 1 }, { 'x': 2 }]
# static unionBy
This method is like _.union except that it accepts iteratee which is
invoked for each element of each arrays to generate the criterion by
which uniqueness is computed. Result values are chosen from the first
array in which the value occurs. The iteratee is invoked with one argument:
(value).
- Since:
- 4.0.0
Example
_.unionBy([2.1], [1.2, 2.3], Math.floor);
// => [2.1, 1.2]
// The `_.property` iteratee shorthand.
_.unionBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x');
// => [{ 'x': 1 }, { 'x': 2 }]
# static unionWith
This method is like _.union except that it accepts comparator which
is invoked to compare elements of arrays. Result values are chosen from
the first array in which the value occurs. The comparator is invoked
with two arguments: (arrVal, othVal).
- Since:
- 4.0.0
Example
var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }];
_.unionWith(objects, others, _.isEqual);
// => [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }, { 'x': 1, 'y': 1 }]
# static unionWith
This method is like _.union except that it accepts comparator which
is invoked to compare elements of arrays. Result values are chosen from
the first array in which the value occurs. The comparator is invoked
with two arguments: (arrVal, othVal).
- Since:
- 4.0.0
Example
var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }];
_.unionWith(objects, others, _.isEqual);
// => [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }, { 'x': 1, 'y': 1 }]
# static upperCase
Converts string, as space separated words, to upper case.
- Since:
- 4.0.0
Example
_.upperCase('--foo-bar');
// => 'FOO BAR'
_.upperCase('fooBar');
// => 'FOO BAR'
_.upperCase('__foo_bar__');
// => 'FOO BAR'
# static upperCase
Converts string, as space separated words, to upper case.
- Since:
- 4.0.0
Example
_.upperCase('--foo-bar');
// => 'FOO BAR'
_.upperCase('fooBar');
// => 'FOO BAR'
_.upperCase('__foo_bar__');
// => 'FOO BAR'
# static upperFirst
Converts the first character of string to upper case.
- Since:
- 4.0.0
Example
_.upperFirst('fred');
// => 'Fred'
_.upperFirst('FRED');
// => 'FRED'
# static upperFirst
Converts the first character of string to upper case.
- Since:
- 4.0.0
Example
_.upperFirst('fred');
// => 'Fred'
_.upperFirst('FRED');
// => 'FRED'
# static without
Creates an array excluding all given values using
SameValueZero
for equality comparisons.
Note: Unlike _.pull, this method returns a new array.
- Since:
- 0.1.0
- See:
-
- _.difference, _.xor
Example
_.without([2, 1, 2, 3], 1, 2);
// => [3]
# static without
Creates an array excluding all given values using
SameValueZero
for equality comparisons.
Note: Unlike _.pull, this method returns a new array.
- Since:
- 0.1.0
- See:
-
- _.difference, _.xor
Example
_.without([2, 1, 2, 3], 1, 2);
// => [3]
# static xor
Creates an array of unique values that is the symmetric difference of the given arrays. The order of result values is determined by the order they occur in the arrays.
- Since:
- 2.4.0
- See:
-
- _.difference, _.without
Example
_.xor([2, 1], [2, 3]);
// => [1, 3]
# static xor
Creates an array of unique values that is the symmetric difference of the given arrays. The order of result values is determined by the order they occur in the arrays.
- Since:
- 2.4.0
- See:
-
- _.difference, _.without
Example
_.xor([2, 1], [2, 3]);
// => [1, 3]
# static xorBy
This method is like _.xor except that it accepts iteratee which is
invoked for each element of each arrays to generate the criterion by
which by which they're compared. The order of result values is determined
by the order they occur in the arrays. The iteratee is invoked with one
argument: (value).
- Since:
- 4.0.0
Example
_.xorBy([2.1, 1.2], [2.3, 3.4], Math.floor);
// => [1.2, 3.4]
// The `_.property` iteratee shorthand.
_.xorBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x');
// => [{ 'x': 2 }]
# static xorBy
This method is like _.xor except that it accepts iteratee which is
invoked for each element of each arrays to generate the criterion by
which by which they're compared. The order of result values is determined
by the order they occur in the arrays. The iteratee is invoked with one
argument: (value).
- Since:
- 4.0.0
Example
_.xorBy([2.1, 1.2], [2.3, 3.4], Math.floor);
// => [1.2, 3.4]
// The `_.property` iteratee shorthand.
_.xorBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x');
// => [{ 'x': 2 }]
# static xorWith
This method is like _.xor except that it accepts comparator which is
invoked to compare elements of arrays. The order of result values is
determined by the order they occur in the arrays. The comparator is invoked
with two arguments: (arrVal, othVal).
- Since:
- 4.0.0
Example
var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }];
_.xorWith(objects, others, _.isEqual);
// => [{ 'x': 2, 'y': 1 }, { 'x': 1, 'y': 1 }]
# static xorWith
This method is like _.xor except that it accepts comparator which is
invoked to compare elements of arrays. The order of result values is
determined by the order they occur in the arrays. The comparator is invoked
with two arguments: (arrVal, othVal).
- Since:
- 4.0.0
Example
var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }];
_.xorWith(objects, others, _.isEqual);
// => [{ 'x': 2, 'y': 1 }, { 'x': 1, 'y': 1 }]
# static zip
Creates an array of grouped elements, the first of which contains the first elements of the given arrays, the second of which contains the second elements of the given arrays, and so on.
- Since:
- 0.1.0
Example
_.zip(['a', 'b'], [1, 2], [true, false]);
// => [['a', 1, true], ['b', 2, false]]
# static zip
Creates an array of grouped elements, the first of which contains the first elements of the given arrays, the second of which contains the second elements of the given arrays, and so on.
- Since:
- 0.1.0
Example
_.zip(['a', 'b'], [1, 2], [true, false]);
// => [['a', 1, true], ['b', 2, false]]
# static zipWith
This method is like _.zip except that it accepts iteratee to specify
how grouped values should be combined. The iteratee is invoked with the
elements of each group: (...group).
- Since:
- 3.8.0
Example
_.zipWith([1, 2], [10, 20], [100, 200], function(a, b, c) {
return a + b + c;
});
// => [111, 222]
# static zipWith
This method is like _.zip except that it accepts iteratee to specify
how grouped values should be combined. The iteratee is invoked with the
elements of each group: (...group).
- Since:
- 3.8.0
Example
_.zipWith([1, 2], [10, 20], [100, 200], function(a, b, c) {
return a + b + c;
});
// => [111, 222]
# value
Executes the chain sequence to resolve the unwrapped value.
- Since:
- 0.1.0
Example
_([1, 2, 3]).value();
// => [1, 2, 3]
# value
Executes the chain sequence to resolve the unwrapped value.
- Since:
- 0.1.0
Example
_([1, 2, 3]).value();
// => [1, 2, 3]
# value
Executes the chain sequence to resolve the unwrapped value.
- Since:
- 0.1.0
Example
_([1, 2, 3]).value();
// => [1, 2, 3]
Methods
# static after(n, func) → {function}
The opposite of _.before; this method creates a function that invokes
func once it's called n or more times.
Parameters:
| Name | Type | Description |
|---|---|---|
n |
number | The number of calls before |
func |
function | The function to restrict. |
- Since:
- 0.1.0
Returns the new restricted function.
Example
var saves = ['profile', 'settings'];
var done = _.after(saves.length, function() {
console.log('done saving!');
});
_.forEach(saves, function(type) {
asyncSave({ 'type': type, 'complete': done });
});
// => Logs 'done saving!' after the two async saves have completed.
# static after(n, func) → {function}
The opposite of _.before; this method creates a function that invokes
func once it's called n or more times.
Parameters:
| Name | Type | Description |
|---|---|---|
n |
number | The number of calls before |
func |
function | The function to restrict. |
- Since:
- 0.1.0
Returns the new restricted function.
Example
var saves = ['profile', 'settings'];
var done = _.after(saves.length, function() {
console.log('done saving!');
});
_.forEach(saves, function(type) {
asyncSave({ 'type': type, 'complete': done });
});
// => Logs 'done saving!' after the two async saves have completed.
# static ary(func, nopt) → {function}
Creates a function that invokes func, with up to n arguments,
ignoring any additional arguments.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
function | The function to cap arguments for. |
||
n |
number |
<optional> |
func.length | The arity cap. |
- Since:
- 3.0.0
Returns the new capped function.
Example
_.map(['6', '8', '10'], _.ary(parseInt, 1));
// => [6, 8, 10]
# static ary(func, nopt) → {function}
Creates a function that invokes func, with up to n arguments,
ignoring any additional arguments.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
function | The function to cap arguments for. |
||
n |
number |
<optional> |
func.length | The arity cap. |
- Since:
- 3.0.0
Returns the new capped function.
Example
_.map(['6', '8', '10'], _.ary(parseInt, 1));
// => [6, 8, 10]
# static before(n, func) → {function}
Creates a function that invokes func, with the this binding and arguments
of the created function, while it's called less than n times. Subsequent
calls to the created function return the result of the last func invocation.
Parameters:
| Name | Type | Description |
|---|---|---|
n |
number | The number of calls at which |
func |
function | The function to restrict. |
- Since:
- 3.0.0
Returns the new restricted function.
Example
jQuery(element).on('click', _.before(5, addContactToList));
// => Allows adding up to 4 contacts to the list.
# static before(n, func) → {function}
Creates a function that invokes func, with the this binding and arguments
of the created function, while it's called less than n times. Subsequent
calls to the created function return the result of the last func invocation.
Parameters:
| Name | Type | Description |
|---|---|---|
n |
number | The number of calls at which |
func |
function | The function to restrict. |
- Since:
- 3.0.0
Returns the new restricted function.
Example
jQuery(element).on('click', _.before(5, addContactToList));
// => Allows adding up to 4 contacts to the list.
# static before(n, func) → {function}
Creates a function that invokes func, with the this binding and arguments
of the created function, while it's called less than n times. Subsequent
calls to the created function return the result of the last func invocation.
Parameters:
| Name | Type | Description |
|---|---|---|
n |
number | The number of calls at which |
func |
function | The function to restrict. |
- Since:
- 3.0.0
Returns the new restricted function.
Example
jQuery(element).on('click', _.before(5, addContactToList));
// => Allows adding up to 4 contacts to the list.
# static capitalize(stringopt) → {string}
Converts the first character of string to upper case and the remaining
to lower case.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to capitalize. |
- Since:
- 3.0.0
Returns the capitalized string.
Example
_.capitalize('FRED');
// => 'Fred'
# static capitalize(stringopt) → {string}
Converts the first character of string to upper case and the remaining
to lower case.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to capitalize. |
- Since:
- 3.0.0
Returns the capitalized string.
Example
_.capitalize('FRED');
// => 'Fred'
# static castArray(value) → {Array}
Casts value as an array if it's not one.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to inspect. |
- Since:
- 4.4.0
Returns the cast array.
Example
_.castArray(1);
// => [1]
_.castArray({ 'a': 1 });
// => [{ 'a': 1 }]
_.castArray('abc');
// => ['abc']
_.castArray(null);
// => [null]
_.castArray(undefined);
// => [undefined]
_.castArray();
// => []
var array = [1, 2, 3];
console.log(_.castArray(array) === array);
// => true
# static castArray(value) → {Array}
Casts value as an array if it's not one.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to inspect. |
- Since:
- 4.4.0
Returns the cast array.
Example
_.castArray(1);
// => [1]
_.castArray({ 'a': 1 });
// => [{ 'a': 1 }]
_.castArray('abc');
// => ['abc']
_.castArray(null);
// => [null]
_.castArray(undefined);
// => [undefined]
_.castArray();
// => []
var array = [1, 2, 3];
console.log(_.castArray(array) === array);
// => true
# static chain(value) → {Object}
Creates a lodash wrapper instance that wraps value with explicit method
chain sequences enabled. The result of such sequences must be unwrapped
with _#value.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to wrap. |
- Since:
- 1.3.0
Returns the new lodash wrapper instance.
Example
var users = [
{ 'user': 'barney', 'age': 36 },
{ 'user': 'fred', 'age': 40 },
{ 'user': 'pebbles', 'age': 1 }
];
var youngest = _
.chain(users)
.sortBy('age')
.map(function(o) {
return o.user + ' is ' + o.age;
})
.head()
.value();
// => 'pebbles is 1'
# static chain(value) → {Object}
Creates a lodash wrapper instance that wraps value with explicit method
chain sequences enabled. The result of such sequences must be unwrapped
with _#value.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to wrap. |
- Since:
- 1.3.0
Returns the new lodash wrapper instance.
Example
var users = [
{ 'user': 'barney', 'age': 36 },
{ 'user': 'fred', 'age': 40 },
{ 'user': 'pebbles', 'age': 1 }
];
var youngest = _
.chain(users)
.sortBy('age')
.map(function(o) {
return o.user + ' is ' + o.age;
})
.head()
.value();
// => 'pebbles is 1'
# static chain(value) → {Object}
Creates a lodash wrapper instance that wraps value with explicit method
chain sequences enabled. The result of such sequences must be unwrapped
with _#value.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to wrap. |
- Since:
- 1.3.0
Returns the new lodash wrapper instance.
Example
var users = [
{ 'user': 'barney', 'age': 36 },
{ 'user': 'fred', 'age': 40 },
{ 'user': 'pebbles', 'age': 1 }
];
var youngest = _
.chain(users)
.sortBy('age')
.map(function(o) {
return o.user + ' is ' + o.age;
})
.head()
.value();
// => 'pebbles is 1'
# static chunk(array, sizeopt) → {Array}
Creates an array of elements split into groups the length of size.
If array can't be split evenly, the final chunk will be the remaining
elements.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to process. |
||
size |
number |
<optional> |
1 | The length of each chunk |
- Since:
- 3.0.0
Returns the new array of chunks.
Example
_.chunk(['a', 'b', 'c', 'd'], 2);
// => [['a', 'b'], ['c', 'd']]
_.chunk(['a', 'b', 'c', 'd'], 3);
// => [['a', 'b', 'c'], ['d']]
# static chunk(array, sizeopt) → {Array}
Creates an array of elements split into groups the length of size.
If array can't be split evenly, the final chunk will be the remaining
elements.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to process. |
||
size |
number |
<optional> |
1 | The length of each chunk |
- Since:
- 3.0.0
Returns the new array of chunks.
Example
_.chunk(['a', 'b', 'c', 'd'], 2);
// => [['a', 'b'], ['c', 'd']]
_.chunk(['a', 'b', 'c', 'd'], 3);
// => [['a', 'b', 'c'], ['d']]
# static clamp(number, loweropt, upper) → {number}
Clamps number within the inclusive lower and upper bounds.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
number |
number | The number to clamp. |
|
lower |
number |
<optional> |
The lower bound. |
upper |
number | The upper bound. |
- Since:
- 4.0.0
Returns the clamped number.
Example
_.clamp(-10, -5, 5);
// => -5
_.clamp(10, -5, 5);
// => 5
# static clamp(number, loweropt, upper) → {number}
Clamps number within the inclusive lower and upper bounds.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
number |
number | The number to clamp. |
|
lower |
number |
<optional> |
The lower bound. |
upper |
number | The upper bound. |
- Since:
- 4.0.0
Returns the clamped number.
Example
_.clamp(-10, -5, 5);
// => -5
_.clamp(10, -5, 5);
// => 5
# static clone(value) → {*}
Creates a shallow clone of value.
Note: This method is loosely based on the
structured clone algorithm
and supports cloning arrays, array buffers, booleans, date objects, maps,
numbers, Object objects, regexes, sets, strings, symbols, and typed
arrays. The own enumerable properties of arguments objects are cloned
as plain objects. An empty object is returned for uncloneable values such
as error objects, functions, DOM nodes, and WeakMaps.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to clone. |
- Since:
- 0.1.0
- See:
Returns the cloned value.
Example
var objects = [{ 'a': 1 }, { 'b': 2 }];
var shallow = _.clone(objects);
console.log(shallow[0] === objects[0]);
// => true
# static clone(value) → {*}
Creates a shallow clone of value.
Note: This method is loosely based on the
structured clone algorithm
and supports cloning arrays, array buffers, booleans, date objects, maps,
numbers, Object objects, regexes, sets, strings, symbols, and typed
arrays. The own enumerable properties of arguments objects are cloned
as plain objects. An empty object is returned for uncloneable values such
as error objects, functions, DOM nodes, and WeakMaps.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to clone. |
- Since:
- 0.1.0
- See:
Returns the cloned value.
Example
var objects = [{ 'a': 1 }, { 'b': 2 }];
var shallow = _.clone(objects);
console.log(shallow[0] === objects[0]);
// => true
# static clone(value) → {*}
Creates a shallow clone of value.
Note: This method is loosely based on the
structured clone algorithm
and supports cloning arrays, array buffers, booleans, date objects, maps,
numbers, Object objects, regexes, sets, strings, symbols, and typed
arrays. The own enumerable properties of arguments objects are cloned
as plain objects. An empty object is returned for uncloneable values such
as error objects, functions, DOM nodes, and WeakMaps.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to clone. |
- Since:
- 0.1.0
- See:
Returns the cloned value.
Example
var objects = [{ 'a': 1 }, { 'b': 2 }];
var shallow = _.clone(objects);
console.log(shallow[0] === objects[0]);
// => true
# static cloneDeep(value) → {*}
This method is like _.clone except that it recursively clones value.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to recursively clone. |
- Since:
- 1.0.0
- See:
Returns the deep cloned value.
Example
var objects = [{ 'a': 1 }, { 'b': 2 }];
var deep = _.cloneDeep(objects);
console.log(deep[0] === objects[0]);
// => false
# static cloneDeep(value) → {*}
This method is like _.clone except that it recursively clones value.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to recursively clone. |
- Since:
- 1.0.0
- See:
Returns the deep cloned value.
Example
var objects = [{ 'a': 1 }, { 'b': 2 }];
var deep = _.cloneDeep(objects);
console.log(deep[0] === objects[0]);
// => false
# static cloneDeepWith(value, customizeropt) → {*}
This method is like _.cloneWith except that it recursively clones value.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
value |
* | The value to recursively clone. |
|
customizer |
function |
<optional> |
The function to customize cloning. |
- Since:
- 4.0.0
- See:
Returns the deep cloned value.
Example
function customizer(value) {
if (_.isElement(value)) {
return value.cloneNode(true);
}
}
var el = _.cloneDeepWith(document.body, customizer);
console.log(el === document.body);
// => false
console.log(el.nodeName);
// => 'BODY'
console.log(el.childNodes.length);
// => 20
# static cloneDeepWith(value, customizeropt) → {*}
This method is like _.cloneWith except that it recursively clones value.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
value |
* | The value to recursively clone. |
|
customizer |
function |
<optional> |
The function to customize cloning. |
- Since:
- 4.0.0
- See:
Returns the deep cloned value.
Example
function customizer(value) {
if (_.isElement(value)) {
return value.cloneNode(true);
}
}
var el = _.cloneDeepWith(document.body, customizer);
console.log(el === document.body);
// => false
console.log(el.nodeName);
// => 'BODY'
console.log(el.childNodes.length);
// => 20
# static cloneWith(value, customizeropt) → {*}
This method is like _.clone except that it accepts customizer which
is invoked to produce the cloned value. If customizer returns undefined,
cloning is handled by the method instead. The customizer is invoked with
up to four arguments; (value [, index|key, object, stack]).
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
value |
* | The value to clone. |
|
customizer |
function |
<optional> |
The function to customize cloning. |
- Since:
- 4.0.0
- See:
Returns the cloned value.
Example
function customizer(value) {
if (_.isElement(value)) {
return value.cloneNode(false);
}
}
var el = _.cloneWith(document.body, customizer);
console.log(el === document.body);
// => false
console.log(el.nodeName);
// => 'BODY'
console.log(el.childNodes.length);
// => 0
# static cloneWith(value, customizeropt) → {*}
This method is like _.clone except that it accepts customizer which
is invoked to produce the cloned value. If customizer returns undefined,
cloning is handled by the method instead. The customizer is invoked with
up to four arguments; (value [, index|key, object, stack]).
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
value |
* | The value to clone. |
|
customizer |
function |
<optional> |
The function to customize cloning. |
- Since:
- 4.0.0
- See:
Returns the cloned value.
Example
function customizer(value) {
if (_.isElement(value)) {
return value.cloneNode(false);
}
}
var el = _.cloneWith(document.body, customizer);
console.log(el === document.body);
// => false
console.log(el.nodeName);
// => 'BODY'
console.log(el.childNodes.length);
// => 0
# static compact(array) → {Array}
Creates an array with all falsey values removed. The values false, null,
0, "", undefined, and NaN are falsey.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to compact. |
- Since:
- 0.1.0
Returns the new array of filtered values.
Example
_.compact([0, 1, false, 2, '', 3]);
// => [1, 2, 3]
# static compact(array) → {Array}
Creates an array with all falsey values removed. The values false, null,
0, "", undefined, and NaN are falsey.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to compact. |
- Since:
- 0.1.0
Returns the new array of filtered values.
Example
_.compact([0, 1, false, 2, '', 3]);
// => [1, 2, 3]
# static compact(array) → {Array}
Creates an array with all falsey values removed. The values false, null,
0, "", undefined, and NaN are falsey.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to compact. |
- Since:
- 0.1.0
Returns the new array of filtered values.
Example
_.compact([0, 1, false, 2, '', 3]);
// => [1, 2, 3]
# static concat(array, …valuesopt) → {Array}
Creates a new array concatenating array with any additional arrays
and/or values.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
array |
Array | The array to concatenate. |
|
values |
* |
<optional> <repeatable> |
The values to concatenate. |
- Since:
- 4.0.0
Returns the new concatenated array.
Example
var array = [1];
var other = _.concat(array, 2, [3], [[4]]);
console.log(other);
// => [1, 2, 3, [4]]
console.log(array);
// => [1]
# static concat(array, …valuesopt) → {Array}
Creates a new array concatenating array with any additional arrays
and/or values.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
array |
Array | The array to concatenate. |
|
values |
* |
<optional> <repeatable> |
The values to concatenate. |
- Since:
- 4.0.0
Returns the new concatenated array.
Example
var array = [1];
var other = _.concat(array, 2, [3], [[4]]);
console.log(other);
// => [1, 2, 3, [4]]
console.log(array);
// => [1]
# static concat(array, …valuesopt) → {Array}
Creates a new array concatenating array with any additional arrays
and/or values.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
array |
Array | The array to concatenate. |
|
values |
* |
<optional> <repeatable> |
The values to concatenate. |
- Since:
- 4.0.0
Returns the new concatenated array.
Example
var array = [1];
var other = _.concat(array, 2, [3], [[4]]);
console.log(other);
// => [1, 2, 3, [4]]
console.log(array);
// => [1]
# static cond(pairs) → {function}
Creates a function that iterates over pairs and invokes the corresponding
function of the first predicate to return truthy. The predicate-function
pairs are invoked with the this binding and arguments of the created
function.
Parameters:
| Name | Type | Description |
|---|---|---|
pairs |
Array | The predicate-function pairs. |
- Since:
- 4.0.0
Returns the new composite function.
Example
var func = _.cond([
[_.matches({ 'a': 1 }), _.constant('matches A')],
[_.conforms({ 'b': _.isNumber }), _.constant('matches B')],
[_.stubTrue, _.constant('no match')]
]);
func({ 'a': 1, 'b': 2 });
// => 'matches A'
func({ 'a': 0, 'b': 1 });
// => 'matches B'
func({ 'a': '1', 'b': '2' });
// => 'no match'
# static cond(pairs) → {function}
Creates a function that iterates over pairs and invokes the corresponding
function of the first predicate to return truthy. The predicate-function
pairs are invoked with the this binding and arguments of the created
function.
Parameters:
| Name | Type | Description |
|---|---|---|
pairs |
Array | The predicate-function pairs. |
- Since:
- 4.0.0
Returns the new composite function.
Example
var func = _.cond([
[_.matches({ 'a': 1 }), _.constant('matches A')],
[_.conforms({ 'b': _.isNumber }), _.constant('matches B')],
[_.stubTrue, _.constant('no match')]
]);
func({ 'a': 1, 'b': 2 });
// => 'matches A'
func({ 'a': 0, 'b': 1 });
// => 'matches B'
func({ 'a': '1', 'b': '2' });
// => 'no match'
# static conforms(source) → {function}
Creates a function that invokes the predicate properties of source with
the corresponding property values of a given object, returning true if
all predicates return truthy, else false.
Note: The created function is equivalent to _.conformsTo with
source partially applied.
Parameters:
| Name | Type | Description |
|---|---|---|
source |
Object | The object of property predicates to conform to. |
- Since:
- 4.0.0
Returns the new spec function.
Example
var objects = [
{ 'a': 2, 'b': 1 },
{ 'a': 1, 'b': 2 }
];
_.filter(objects, _.conforms({ 'b': function(n) { return n > 1; } }));
// => [{ 'a': 1, 'b': 2 }]
# static conforms(source) → {function}
Creates a function that invokes the predicate properties of source with
the corresponding property values of a given object, returning true if
all predicates return truthy, else false.
Note: The created function is equivalent to _.conformsTo with
source partially applied.
Parameters:
| Name | Type | Description |
|---|---|---|
source |
Object | The object of property predicates to conform to. |
- Since:
- 4.0.0
Returns the new spec function.
Example
var objects = [
{ 'a': 2, 'b': 1 },
{ 'a': 1, 'b': 2 }
];
_.filter(objects, _.conforms({ 'b': function(n) { return n > 1; } }));
// => [{ 'a': 1, 'b': 2 }]
# static conformsTo(object, source) → {boolean}
Checks if object conforms to source by invoking the predicate
properties of source with the corresponding property values of object.
Note: This method is equivalent to _.conforms when source is
partially applied.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to inspect. |
source |
Object | The object of property predicates to conform to. |
- Since:
- 4.14.0
Returns true if object conforms, else false.
Example
var object = { 'a': 1, 'b': 2 };
_.conformsTo(object, { 'b': function(n) { return n > 1; } });
// => true
_.conformsTo(object, { 'b': function(n) { return n > 2; } });
// => false
# static conformsTo(object, source) → {boolean}
Checks if object conforms to source by invoking the predicate
properties of source with the corresponding property values of object.
Note: This method is equivalent to _.conforms when source is
partially applied.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to inspect. |
source |
Object | The object of property predicates to conform to. |
- Since:
- 4.14.0
Returns true if object conforms, else false.
Example
var object = { 'a': 1, 'b': 2 };
_.conformsTo(object, { 'b': function(n) { return n > 1; } });
// => true
_.conformsTo(object, { 'b': function(n) { return n > 2; } });
// => false
# static constant(value) → {function}
Creates a function that returns value.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to return from the new function. |
- Since:
- 2.4.0
Returns the new constant function.
Example
var objects = _.times(2, _.constant({ 'a': 1 }));
console.log(objects);
// => [{ 'a': 1 }, { 'a': 1 }]
console.log(objects[0] === objects[1]);
// => true
# static constant(value) → {function}
Creates a function that returns value.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to return from the new function. |
- Since:
- 2.4.0
Returns the new constant function.
Example
var objects = _.times(2, _.constant({ 'a': 1 }));
console.log(objects);
// => [{ 'a': 1 }, { 'a': 1 }]
console.log(objects[0] === objects[1]);
// => true
# static create(prototype, propertiesopt) → {Object}
Creates an object that inherits from the prototype object. If a
properties object is given, its own enumerable string keyed properties
are assigned to the created object.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
prototype |
Object | The object to inherit from. |
|
properties |
Object |
<optional> |
The properties to assign to the object. |
- Since:
- 2.3.0
Returns the new object.
Example
function Shape() {
this.x = 0;
this.y = 0;
}
function Circle() {
Shape.call(this);
}
Circle.prototype = _.create(Shape.prototype, {
'constructor': Circle
});
var circle = new Circle;
circle instanceof Circle;
// => true
circle instanceof Shape;
// => true
# static create(prototype, propertiesopt) → {Object}
Creates an object that inherits from the prototype object. If a
properties object is given, its own enumerable string keyed properties
are assigned to the created object.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
prototype |
Object | The object to inherit from. |
|
properties |
Object |
<optional> |
The properties to assign to the object. |
- Since:
- 2.3.0
Returns the new object.
Example
function Shape() {
this.x = 0;
this.y = 0;
}
function Circle() {
Shape.call(this);
}
Circle.prototype = _.create(Shape.prototype, {
'constructor': Circle
});
var circle = new Circle;
circle instanceof Circle;
// => true
circle instanceof Shape;
// => true
# static create(prototype, propertiesopt) → {Object}
Creates an object that inherits from the prototype object. If a
properties object is given, its own enumerable string keyed properties
are assigned to the created object.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
prototype |
Object | The object to inherit from. |
|
properties |
Object |
<optional> |
The properties to assign to the object. |
- Since:
- 2.3.0
Returns the new object.
Example
function Shape() {
this.x = 0;
this.y = 0;
}
function Circle() {
Shape.call(this);
}
Circle.prototype = _.create(Shape.prototype, {
'constructor': Circle
});
var circle = new Circle;
circle instanceof Circle;
// => true
circle instanceof Shape;
// => true
# static curry(func, arityopt) → {function}
Creates a function that accepts arguments of func and either invokes
func returning its result, if at least arity number of arguments have
been provided, or returns a function that accepts the remaining func
arguments, and so on. The arity of func may be specified if func.length
is not sufficient.
The _.curry.placeholder value, which defaults to _ in monolithic builds,
may be used as a placeholder for provided arguments.
Note: This method doesn't set the "length" property of curried functions.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
function | The function to curry. |
||
arity |
number |
<optional> |
func.length | The arity of |
- Since:
- 2.0.0
Returns the new curried function.
Example
var abc = function(a, b, c) {
return [a, b, c];
};
var curried = _.curry(abc);
curried(1)(2)(3);
// => [1, 2, 3]
curried(1, 2)(3);
// => [1, 2, 3]
curried(1, 2, 3);
// => [1, 2, 3]
// Curried with placeholders.
curried(1)(_, 3)(2);
// => [1, 2, 3]
# static curry(func, arityopt) → {function}
Creates a function that accepts arguments of func and either invokes
func returning its result, if at least arity number of arguments have
been provided, or returns a function that accepts the remaining func
arguments, and so on. The arity of func may be specified if func.length
is not sufficient.
The _.curry.placeholder value, which defaults to _ in monolithic builds,
may be used as a placeholder for provided arguments.
Note: This method doesn't set the "length" property of curried functions.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
function | The function to curry. |
||
arity |
number |
<optional> |
func.length | The arity of |
- Since:
- 2.0.0
Returns the new curried function.
Example
var abc = function(a, b, c) {
return [a, b, c];
};
var curried = _.curry(abc);
curried(1)(2)(3);
// => [1, 2, 3]
curried(1, 2)(3);
// => [1, 2, 3]
curried(1, 2, 3);
// => [1, 2, 3]
// Curried with placeholders.
curried(1)(_, 3)(2);
// => [1, 2, 3]
# static curryRight(func, arityopt) → {function}
This method is like _.curry except that arguments are applied to func
in the manner of _.partialRight instead of _.partial.
The _.curryRight.placeholder value, which defaults to _ in monolithic
builds, may be used as a placeholder for provided arguments.
Note: This method doesn't set the "length" property of curried functions.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
function | The function to curry. |
||
arity |
number |
<optional> |
func.length | The arity of |
- Since:
- 3.0.0
Returns the new curried function.
Example
var abc = function(a, b, c) {
return [a, b, c];
};
var curried = _.curryRight(abc);
curried(3)(2)(1);
// => [1, 2, 3]
curried(2, 3)(1);
// => [1, 2, 3]
curried(1, 2, 3);
// => [1, 2, 3]
// Curried with placeholders.
curried(3)(1, _)(2);
// => [1, 2, 3]
# static curryRight(func, arityopt) → {function}
This method is like _.curry except that arguments are applied to func
in the manner of _.partialRight instead of _.partial.
The _.curryRight.placeholder value, which defaults to _ in monolithic
builds, may be used as a placeholder for provided arguments.
Note: This method doesn't set the "length" property of curried functions.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
function | The function to curry. |
||
arity |
number |
<optional> |
func.length | The arity of |
- Since:
- 3.0.0
Returns the new curried function.
Example
var abc = function(a, b, c) {
return [a, b, c];
};
var curried = _.curryRight(abc);
curried(3)(2)(1);
// => [1, 2, 3]
curried(2, 3)(1);
// => [1, 2, 3]
curried(1, 2, 3);
// => [1, 2, 3]
// Curried with placeholders.
curried(3)(1, _)(2);
// => [1, 2, 3]
# static debounce(func, waitopt, optionsopt) → {function}
Creates a debounced function that delays invoking func until after wait
milliseconds have elapsed since the last time the debounced function was
invoked. The debounced function comes with a cancel method to cancel
delayed func invocations and a flush method to immediately invoke them.
Provide options to indicate whether func should be invoked on the
leading and/or trailing edge of the wait timeout. The func is invoked
with the last arguments provided to the debounced function. Subsequent
calls to the debounced function return the result of the last func
invocation.
Note: If leading and trailing options are true, func is
invoked on the trailing edge of the timeout only if the debounced function
is invoked more than once during the wait timeout.
If wait is 0 and leading is false, func invocation is deferred
until to the next tick, similar to setTimeout with a timeout of 0.
See David Corbacho's article
for details over the differences between _.debounce and _.throttle.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
function | The function to debounce. |
||
wait |
number |
<optional> |
0 | The number of milliseconds to delay. |
options |
Object |
<optional> |
{} | The options object. |
leading |
boolean |
<optional> |
false | Specify invoking on the leading edge of the timeout. |
maxWait |
number |
<optional> |
The maximum time |
|
trailing |
boolean |
<optional> |
true | Specify invoking on the trailing edge of the timeout. |
- Since:
- 0.1.0
Returns the new debounced function.
Example
// Avoid costly calculations while the window size is in flux.
jQuery(window).on('resize', _.debounce(calculateLayout, 150));
// Invoke `sendMail` when clicked, debouncing subsequent calls.
jQuery(element).on('click', _.debounce(sendMail, 300, {
'leading': true,
'trailing': false
}));
// Ensure `batchLog` is invoked once after 1 second of debounced calls.
var debounced = _.debounce(batchLog, 250, { 'maxWait': 1000 });
var source = new EventSource('/stream');
jQuery(source).on('message', debounced);
// Cancel the trailing debounced invocation.
jQuery(window).on('popstate', debounced.cancel);
# static debounce(func, waitopt, optionsopt) → {function}
Creates a debounced function that delays invoking func until after wait
milliseconds have elapsed since the last time the debounced function was
invoked. The debounced function comes with a cancel method to cancel
delayed func invocations and a flush method to immediately invoke them.
Provide options to indicate whether func should be invoked on the
leading and/or trailing edge of the wait timeout. The func is invoked
with the last arguments provided to the debounced function. Subsequent
calls to the debounced function return the result of the last func
invocation.
Note: If leading and trailing options are true, func is
invoked on the trailing edge of the timeout only if the debounced function
is invoked more than once during the wait timeout.
If wait is 0 and leading is false, func invocation is deferred
until to the next tick, similar to setTimeout with a timeout of 0.
See David Corbacho's article
for details over the differences between _.debounce and _.throttle.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
function | The function to debounce. |
||
wait |
number |
<optional> |
0 | The number of milliseconds to delay. |
options |
Object |
<optional> |
{} | The options object. |
leading |
boolean |
<optional> |
false | Specify invoking on the leading edge of the timeout. |
maxWait |
number |
<optional> |
The maximum time |
|
trailing |
boolean |
<optional> |
true | Specify invoking on the trailing edge of the timeout. |
- Since:
- 0.1.0
Returns the new debounced function.
Example
// Avoid costly calculations while the window size is in flux.
jQuery(window).on('resize', _.debounce(calculateLayout, 150));
// Invoke `sendMail` when clicked, debouncing subsequent calls.
jQuery(element).on('click', _.debounce(sendMail, 300, {
'leading': true,
'trailing': false
}));
// Ensure `batchLog` is invoked once after 1 second of debounced calls.
var debounced = _.debounce(batchLog, 250, { 'maxWait': 1000 });
var source = new EventSource('/stream');
jQuery(source).on('message', debounced);
// Cancel the trailing debounced invocation.
jQuery(window).on('popstate', debounced.cancel);
# static deburr(stringopt) → {string}
Deburrs string by converting
Latin-1 Supplement
and Latin Extended-A
letters to basic Latin letters and removing
combining diacritical marks.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to deburr. |
- Since:
- 3.0.0
Returns the deburred string.
Example
_.deburr('déjà vu');
// => 'deja vu'
# static deburr(stringopt) → {string}
Deburrs string by converting
Latin-1 Supplement
and Latin Extended-A
letters to basic Latin letters and removing
combining diacritical marks.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to deburr. |
- Since:
- 3.0.0
Returns the deburred string.
Example
_.deburr('déjà vu');
// => 'deja vu'
# static defaultTo(value, defaultValue) → {*}
Checks value to determine whether a default value should be returned in
its place. The defaultValue is returned if value is NaN, null,
or undefined.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
defaultValue |
* | The default value. |
- Since:
- 4.14.0
Returns the resolved value.
Example
_.defaultTo(1, 10);
// => 1
_.defaultTo(undefined, 10);
// => 10
# static defaultTo(value, defaultValue) → {*}
Checks value to determine whether a default value should be returned in
its place. The defaultValue is returned if value is NaN, null,
or undefined.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
defaultValue |
* | The default value. |
- Since:
- 4.14.0
Returns the resolved value.
Example
_.defaultTo(1, 10);
// => 1
_.defaultTo(undefined, 10);
// => 10
# static drop(array, nopt) → {Array}
Creates a slice of array with n elements dropped from the beginning.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
n |
number |
<optional> |
1 | The number of elements to drop. |
- Since:
- 0.5.0
Returns the slice of array.
Example
_.drop([1, 2, 3]);
// => [2, 3]
_.drop([1, 2, 3], 2);
// => [3]
_.drop([1, 2, 3], 5);
// => []
_.drop([1, 2, 3], 0);
// => [1, 2, 3]
# static drop(array, nopt) → {Array}
Creates a slice of array with n elements dropped from the beginning.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
n |
number |
<optional> |
1 | The number of elements to drop. |
- Since:
- 0.5.0
Returns the slice of array.
Example
_.drop([1, 2, 3]);
// => [2, 3]
_.drop([1, 2, 3], 2);
// => [3]
_.drop([1, 2, 3], 5);
// => []
_.drop([1, 2, 3], 0);
// => [1, 2, 3]
# static dropRight(array, nopt) → {Array}
Creates a slice of array with n elements dropped from the end.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
n |
number |
<optional> |
1 | The number of elements to drop. |
- Since:
- 3.0.0
Returns the slice of array.
Example
_.dropRight([1, 2, 3]);
// => [1, 2]
_.dropRight([1, 2, 3], 2);
// => [1]
_.dropRight([1, 2, 3], 5);
// => []
_.dropRight([1, 2, 3], 0);
// => [1, 2, 3]
# static dropRight(array, nopt) → {Array}
Creates a slice of array with n elements dropped from the end.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
n |
number |
<optional> |
1 | The number of elements to drop. |
- Since:
- 3.0.0
Returns the slice of array.
Example
_.dropRight([1, 2, 3]);
// => [1, 2]
_.dropRight([1, 2, 3], 2);
// => [1]
_.dropRight([1, 2, 3], 5);
// => []
_.dropRight([1, 2, 3], 0);
// => [1, 2, 3]
# static dropRightWhile(array, predicateopt) → {Array}
Creates a slice of array excluding elements dropped from the end.
Elements are dropped until predicate returns falsey. The predicate is
invoked with three arguments: (value, index, array).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 3.0.0
Returns the slice of array.
Example
var users = [
{ 'user': 'barney', 'active': true },
{ 'user': 'fred', 'active': false },
{ 'user': 'pebbles', 'active': false }
];
_.dropRightWhile(users, function(o) { return !o.active; });
// => objects for ['barney']
// The `_.matches` iteratee shorthand.
_.dropRightWhile(users, { 'user': 'pebbles', 'active': false });
// => objects for ['barney', 'fred']
// The `_.matchesProperty` iteratee shorthand.
_.dropRightWhile(users, ['active', false]);
// => objects for ['barney']
// The `_.property` iteratee shorthand.
_.dropRightWhile(users, 'active');
// => objects for ['barney', 'fred', 'pebbles']
# static dropRightWhile(array, predicateopt) → {Array}
Creates a slice of array excluding elements dropped from the end.
Elements are dropped until predicate returns falsey. The predicate is
invoked with three arguments: (value, index, array).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 3.0.0
Returns the slice of array.
Example
var users = [
{ 'user': 'barney', 'active': true },
{ 'user': 'fred', 'active': false },
{ 'user': 'pebbles', 'active': false }
];
_.dropRightWhile(users, function(o) { return !o.active; });
// => objects for ['barney']
// The `_.matches` iteratee shorthand.
_.dropRightWhile(users, { 'user': 'pebbles', 'active': false });
// => objects for ['barney', 'fred']
// The `_.matchesProperty` iteratee shorthand.
_.dropRightWhile(users, ['active', false]);
// => objects for ['barney']
// The `_.property` iteratee shorthand.
_.dropRightWhile(users, 'active');
// => objects for ['barney', 'fred', 'pebbles']
# static dropWhile(array, predicateopt) → {Array}
Creates a slice of array excluding elements dropped from the beginning.
Elements are dropped until predicate returns falsey. The predicate is
invoked with three arguments: (value, index, array).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 3.0.0
Returns the slice of array.
Example
var users = [
{ 'user': 'barney', 'active': false },
{ 'user': 'fred', 'active': false },
{ 'user': 'pebbles', 'active': true }
];
_.dropWhile(users, function(o) { return !o.active; });
// => objects for ['pebbles']
// The `_.matches` iteratee shorthand.
_.dropWhile(users, { 'user': 'barney', 'active': false });
// => objects for ['fred', 'pebbles']
// The `_.matchesProperty` iteratee shorthand.
_.dropWhile(users, ['active', false]);
// => objects for ['pebbles']
// The `_.property` iteratee shorthand.
_.dropWhile(users, 'active');
// => objects for ['barney', 'fred', 'pebbles']
# static dropWhile(array, predicateopt) → {Array}
Creates a slice of array excluding elements dropped from the beginning.
Elements are dropped until predicate returns falsey. The predicate is
invoked with three arguments: (value, index, array).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 3.0.0
Returns the slice of array.
Example
var users = [
{ 'user': 'barney', 'active': false },
{ 'user': 'fred', 'active': false },
{ 'user': 'pebbles', 'active': true }
];
_.dropWhile(users, function(o) { return !o.active; });
// => objects for ['pebbles']
// The `_.matches` iteratee shorthand.
_.dropWhile(users, { 'user': 'barney', 'active': false });
// => objects for ['fred', 'pebbles']
// The `_.matchesProperty` iteratee shorthand.
_.dropWhile(users, ['active', false]);
// => objects for ['pebbles']
// The `_.property` iteratee shorthand.
_.dropWhile(users, 'active');
// => objects for ['barney', 'fred', 'pebbles']
# static each(collection, iterateeopt) → {Array|Object}
Iterates over elements of collection and invokes iteratee for each element.
The iteratee is invoked with three arguments: (value, index|key, collection).
Iteratee functions may exit iteration early by explicitly returning false.
Note: As with other "Collections" methods, objects with a "length"
property are iterated like arrays. To avoid this behavior use _.forIn
or _.forOwn for object iteration.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
- See:
-
- _.forEachRight
Returns collection.
Example
_.forEach([1, 2], function(value) {
console.log(value);
});
// => Logs `1` then `2`.
_.forEach({ 'a': 1, 'b': 2 }, function(value, key) {
console.log(key);
});
// => Logs 'a' then 'b' (iteration order is not guaranteed).
# static each(collection, iterateeopt) → {Array|Object}
Iterates over elements of collection and invokes iteratee for each element.
The iteratee is invoked with three arguments: (value, index|key, collection).
Iteratee functions may exit iteration early by explicitly returning false.
Note: As with other "Collections" methods, objects with a "length"
property are iterated like arrays. To avoid this behavior use _.forIn
or _.forOwn for object iteration.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
- See:
-
- _.forEachRight
Returns collection.
Example
_.forEach([1, 2], function(value) {
console.log(value);
});
// => Logs `1` then `2`.
_.forEach({ 'a': 1, 'b': 2 }, function(value, key) {
console.log(key);
});
// => Logs 'a' then 'b' (iteration order is not guaranteed).
# static each(collection, iterateeopt) → {Array|Object}
Iterates over elements of collection and invokes iteratee for each element.
The iteratee is invoked with three arguments: (value, index|key, collection).
Iteratee functions may exit iteration early by explicitly returning false.
Note: As with other "Collections" methods, objects with a "length"
property are iterated like arrays. To avoid this behavior use _.forIn
or _.forOwn for object iteration.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
- See:
-
- _.forEachRight
Returns collection.
Example
_.forEach([1, 2], function(value) {
console.log(value);
});
// => Logs `1` then `2`.
_.forEach({ 'a': 1, 'b': 2 }, function(value, key) {
console.log(key);
});
// => Logs 'a' then 'b' (iteration order is not guaranteed).
# static eachRight(collection, iterateeopt) → {Array|Object}
This method is like _.forEach except that it iterates over elements of
collection from right to left.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 2.0.0
- See:
-
- _.forEach
Returns collection.
Example
_.forEachRight([1, 2], function(value) {
console.log(value);
});
// => Logs `2` then `1`.
# static eachRight(collection, iterateeopt) → {Array|Object}
This method is like _.forEach except that it iterates over elements of
collection from right to left.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 2.0.0
- See:
-
- _.forEach
Returns collection.
Example
_.forEachRight([1, 2], function(value) {
console.log(value);
});
// => Logs `2` then `1`.
# static endsWith(stringopt, targetopt, positionopt) → {boolean}
Checks if string ends with the given target string.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to inspect. |
target |
string |
<optional> |
The string to search for. |
|
position |
number |
<optional> |
string.length | The position to search up to. |
- Since:
- 3.0.0
Returns true if string ends with target,
else false.
Example
_.endsWith('abc', 'c');
// => true
_.endsWith('abc', 'b');
// => false
_.endsWith('abc', 'b', 2);
// => true
# static endsWith(stringopt, targetopt, positionopt) → {boolean}
Checks if string ends with the given target string.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to inspect. |
target |
string |
<optional> |
The string to search for. |
|
position |
number |
<optional> |
string.length | The position to search up to. |
- Since:
- 3.0.0
Returns true if string ends with target,
else false.
Example
_.endsWith('abc', 'c');
// => true
_.endsWith('abc', 'b');
// => false
_.endsWith('abc', 'b', 2);
// => true
# static eq(value, other) → {boolean}
Performs a
SameValueZero
comparison between two values to determine if they are equivalent.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to compare. |
other |
* | The other value to compare. |
- Since:
- 4.0.0
Returns true if the values are equivalent, else false.
Example
var object = { 'a': 1 };
var other = { 'a': 1 };
_.eq(object, object);
// => true
_.eq(object, other);
// => false
_.eq('a', 'a');
// => true
_.eq('a', Object('a'));
// => false
_.eq(NaN, NaN);
// => true
# static eq(value, other) → {boolean}
Performs a
SameValueZero
comparison between two values to determine if they are equivalent.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to compare. |
other |
* | The other value to compare. |
- Since:
- 4.0.0
Returns true if the values are equivalent, else false.
Example
var object = { 'a': 1 };
var other = { 'a': 1 };
_.eq(object, object);
// => true
_.eq(object, other);
// => false
_.eq('a', 'a');
// => true
_.eq('a', Object('a'));
// => false
_.eq(NaN, NaN);
// => true
# static eq(value, other) → {boolean}
Performs a
SameValueZero
comparison between two values to determine if they are equivalent.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to compare. |
other |
* | The other value to compare. |
- Since:
- 4.0.0
Returns true if the values are equivalent, else false.
Example
var object = { 'a': 1 };
var other = { 'a': 1 };
_.eq(object, object);
// => true
_.eq(object, other);
// => false
_.eq('a', 'a');
// => true
_.eq('a', Object('a'));
// => false
_.eq(NaN, NaN);
// => true
# static escape(stringopt) → {string}
Converts the characters "&", "<", ">", '"', and "'" in string to their
corresponding HTML entities.
Note: No other characters are escaped. To escape additional characters use a third-party library like he.
Though the ">" character is escaped for symmetry, characters like ">" and "/" don't need escaping in HTML and have no special meaning unless they're part of a tag or unquoted attribute value. See Mathias Bynens's article (under "semi-related fun fact") for more details.
When working with HTML you should always quote attribute values to reduce XSS vectors.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to escape. |
- Since:
- 0.1.0
Returns the escaped string.
Example
_.escape('fred, barney, & pebbles');
// => 'fred, barney, & pebbles'
# static escape(stringopt) → {string}
Converts the characters "&", "<", ">", '"', and "'" in string to their
corresponding HTML entities.
Note: No other characters are escaped. To escape additional characters use a third-party library like he.
Though the ">" character is escaped for symmetry, characters like ">" and "/" don't need escaping in HTML and have no special meaning unless they're part of a tag or unquoted attribute value. See Mathias Bynens's article (under "semi-related fun fact") for more details.
When working with HTML you should always quote attribute values to reduce XSS vectors.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to escape. |
- Since:
- 0.1.0
Returns the escaped string.
Example
_.escape('fred, barney, & pebbles');
// => 'fred, barney, & pebbles'
# static escape(stringopt) → {string}
Converts the characters "&", "<", ">", '"', and "'" in string to their
corresponding HTML entities.
Note: No other characters are escaped. To escape additional characters use a third-party library like he.
Though the ">" character is escaped for symmetry, characters like ">" and "/" don't need escaping in HTML and have no special meaning unless they're part of a tag or unquoted attribute value. See Mathias Bynens's article (under "semi-related fun fact") for more details.
When working with HTML you should always quote attribute values to reduce XSS vectors.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to escape. |
- Since:
- 0.1.0
Returns the escaped string.
Example
_.escape('fred, barney, & pebbles');
// => 'fred, barney, & pebbles'
# static escapeRegExp(stringopt) → {string}
Escapes the RegExp special characters "^", "$", "", ".", "*", "+",
"?", "(", ")", "[", "]", "{", "}", and "|" in string.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to escape. |
- Since:
- 3.0.0
Returns the escaped string.
Example
_.escapeRegExp('[lodash](https://lodash.com/)');
// => '\[lodash\]\(https://lodash\.com/\)'
# static escapeRegExp(stringopt) → {string}
Escapes the RegExp special characters "^", "$", "", ".", "*", "+",
"?", "(", ")", "[", "]", "{", "}", and "|" in string.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to escape. |
- Since:
- 3.0.0
Returns the escaped string.
Example
_.escapeRegExp('[lodash](https://lodash.com/)');
// => '\[lodash\]\(https://lodash\.com/\)'
# static every(collection, predicateopt) → {boolean}
Checks if predicate returns truthy for all elements of collection.
Iteration is stopped once predicate returns falsey. The predicate is
invoked with three arguments: (value, index|key, collection).
Note: This method returns true for
empty collections because
everything is true of
elements of empty collections.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
Returns true if all elements pass the predicate check,
else false.
Example
_.every([true, 1, null, 'yes'], Boolean);
// => false
var users = [
{ 'user': 'barney', 'age': 36, 'active': false },
{ 'user': 'fred', 'age': 40, 'active': false }
];
// The `_.matches` iteratee shorthand.
_.every(users, { 'user': 'barney', 'active': false });
// => false
// The `_.matchesProperty` iteratee shorthand.
_.every(users, ['active', false]);
// => true
// The `_.property` iteratee shorthand.
_.every(users, 'active');
// => false
# static every(collection, predicateopt) → {boolean}
Checks if predicate returns truthy for all elements of collection.
Iteration is stopped once predicate returns falsey. The predicate is
invoked with three arguments: (value, index|key, collection).
Note: This method returns true for
empty collections because
everything is true of
elements of empty collections.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
Returns true if all elements pass the predicate check,
else false.
Example
_.every([true, 1, null, 'yes'], Boolean);
// => false
var users = [
{ 'user': 'barney', 'age': 36, 'active': false },
{ 'user': 'fred', 'age': 40, 'active': false }
];
// The `_.matches` iteratee shorthand.
_.every(users, { 'user': 'barney', 'active': false });
// => false
// The `_.matchesProperty` iteratee shorthand.
_.every(users, ['active', false]);
// => true
// The `_.property` iteratee shorthand.
_.every(users, 'active');
// => false
# static every(collection, predicateopt) → {boolean}
Checks if predicate returns truthy for all elements of collection.
Iteration is stopped once predicate returns falsey. The predicate is
invoked with three arguments: (value, index|key, collection).
Note: This method returns true for
empty collections because
everything is true of
elements of empty collections.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
Returns true if all elements pass the predicate check,
else false.
Example
_.every([true, 1, null, 'yes'], Boolean);
// => false
var users = [
{ 'user': 'barney', 'age': 36, 'active': false },
{ 'user': 'fred', 'age': 40, 'active': false }
];
// The `_.matches` iteratee shorthand.
_.every(users, { 'user': 'barney', 'active': false });
// => false
// The `_.matchesProperty` iteratee shorthand.
_.every(users, ['active', false]);
// => true
// The `_.property` iteratee shorthand.
_.every(users, 'active');
// => false
# static fill(array, value, startopt, endopt) → {Array}
Fills elements of array with value from start up to, but not
including, end.
Note: This method mutates array.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to fill. |
||
value |
* | The value to fill |
||
start |
number |
<optional> |
0 | The start position. |
end |
number |
<optional> |
array.length | The end position. |
- Since:
- 3.2.0
Returns array.
Example
var array = [1, 2, 3];
_.fill(array, 'a');
console.log(array);
// => ['a', 'a', 'a']
_.fill(Array(3), 2);
// => [2, 2, 2]
_.fill([4, 6, 8, 10], '*', 1, 3);
// => [4, '*', '*', 10]
# static fill(array, value, startopt, endopt) → {Array}
Fills elements of array with value from start up to, but not
including, end.
Note: This method mutates array.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to fill. |
||
value |
* | The value to fill |
||
start |
number |
<optional> |
0 | The start position. |
end |
number |
<optional> |
array.length | The end position. |
- Since:
- 3.2.0
Returns array.
Example
var array = [1, 2, 3];
_.fill(array, 'a');
console.log(array);
// => ['a', 'a', 'a']
_.fill(Array(3), 2);
// => [2, 2, 2]
_.fill([4, 6, 8, 10], '*', 1, 3);
// => [4, '*', '*', 10]
# static filter(collection, predicateopt) → {Array}
Iterates over elements of collection, returning an array of all elements
predicate returns truthy for. The predicate is invoked with three
arguments: (value, index|key, collection).
Note: Unlike _.remove, this method returns a new array.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
- See:
Returns the new filtered array.
Example
var users = [
{ 'user': 'barney', 'age': 36, 'active': true },
{ 'user': 'fred', 'age': 40, 'active': false }
];
_.filter(users, function(o) { return !o.active; });
// => objects for ['fred']
// The `_.matches` iteratee shorthand.
_.filter(users, { 'age': 36, 'active': true });
// => objects for ['barney']
// The `_.matchesProperty` iteratee shorthand.
_.filter(users, ['active', false]);
// => objects for ['fred']
// The `_.property` iteratee shorthand.
_.filter(users, 'active');
// => objects for ['barney']
// Combining several predicates using `_.overEvery` or `_.overSome`.
_.filter(users, _.overSome([{ 'age': 36 }, ['age', 40]]));
// => objects for ['fred', 'barney']
# static filter(collection, predicateopt) → {Array}
Iterates over elements of collection, returning an array of all elements
predicate returns truthy for. The predicate is invoked with three
arguments: (value, index|key, collection).
Note: Unlike _.remove, this method returns a new array.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
- See:
Returns the new filtered array.
Example
var users = [
{ 'user': 'barney', 'age': 36, 'active': true },
{ 'user': 'fred', 'age': 40, 'active': false }
];
_.filter(users, function(o) { return !o.active; });
// => objects for ['fred']
// The `_.matches` iteratee shorthand.
_.filter(users, { 'age': 36, 'active': true });
// => objects for ['barney']
// The `_.matchesProperty` iteratee shorthand.
_.filter(users, ['active', false]);
// => objects for ['fred']
// The `_.property` iteratee shorthand.
_.filter(users, 'active');
// => objects for ['barney']
// Combining several predicates using `_.overEvery` or `_.overSome`.
_.filter(users, _.overSome([{ 'age': 36 }, ['age', 40]]));
// => objects for ['fred', 'barney']
# static filter(collection, predicateopt) → {Array}
Iterates over elements of collection, returning an array of all elements
predicate returns truthy for. The predicate is invoked with three
arguments: (value, index|key, collection).
Note: Unlike _.remove, this method returns a new array.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
- See:
Returns the new filtered array.
Example
var users = [
{ 'user': 'barney', 'age': 36, 'active': true },
{ 'user': 'fred', 'age': 40, 'active': false }
];
_.filter(users, function(o) { return !o.active; });
// => objects for ['fred']
// The `_.matches` iteratee shorthand.
_.filter(users, { 'age': 36, 'active': true });
// => objects for ['barney']
// The `_.matchesProperty` iteratee shorthand.
_.filter(users, ['active', false]);
// => objects for ['fred']
// The `_.property` iteratee shorthand.
_.filter(users, 'active');
// => objects for ['barney']
// Combining several predicates using `_.overEvery` or `_.overSome`.
_.filter(users, _.overSome([{ 'age': 36 }, ['age', 40]]));
// => objects for ['fred', 'barney']
# static findIndex(array, predicateopt, fromIndexopt) → {number}
This method is like _.find except that it returns the index of the first
element predicate returns truthy for instead of the element itself.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to inspect. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
fromIndex |
number |
<optional> |
0 | The index to search from. |
- Since:
- 1.1.0
Returns the index of the found element, else -1.
Example
var users = [
{ 'user': 'barney', 'active': false },
{ 'user': 'fred', 'active': false },
{ 'user': 'pebbles', 'active': true }
];
_.findIndex(users, function(o) { return o.user == 'barney'; });
// => 0
// The `_.matches` iteratee shorthand.
_.findIndex(users, { 'user': 'fred', 'active': false });
// => 1
// The `_.matchesProperty` iteratee shorthand.
_.findIndex(users, ['active', false]);
// => 0
// The `_.property` iteratee shorthand.
_.findIndex(users, 'active');
// => 2
# static findIndex(array, predicateopt, fromIndexopt) → {number}
This method is like _.find except that it returns the index of the first
element predicate returns truthy for instead of the element itself.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to inspect. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
fromIndex |
number |
<optional> |
0 | The index to search from. |
- Since:
- 1.1.0
Returns the index of the found element, else -1.
Example
var users = [
{ 'user': 'barney', 'active': false },
{ 'user': 'fred', 'active': false },
{ 'user': 'pebbles', 'active': true }
];
_.findIndex(users, function(o) { return o.user == 'barney'; });
// => 0
// The `_.matches` iteratee shorthand.
_.findIndex(users, { 'user': 'fred', 'active': false });
// => 1
// The `_.matchesProperty` iteratee shorthand.
_.findIndex(users, ['active', false]);
// => 0
// The `_.property` iteratee shorthand.
_.findIndex(users, 'active');
// => 2
# static findIndex(array, predicateopt, fromIndexopt) → {number}
This method is like _.find except that it returns the index of the first
element predicate returns truthy for instead of the element itself.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to inspect. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
fromIndex |
number |
<optional> |
0 | The index to search from. |
- Since:
- 1.1.0
Returns the index of the found element, else -1.
Example
var users = [
{ 'user': 'barney', 'active': false },
{ 'user': 'fred', 'active': false },
{ 'user': 'pebbles', 'active': true }
];
_.findIndex(users, function(o) { return o.user == 'barney'; });
// => 0
// The `_.matches` iteratee shorthand.
_.findIndex(users, { 'user': 'fred', 'active': false });
// => 1
// The `_.matchesProperty` iteratee shorthand.
_.findIndex(users, ['active', false]);
// => 0
// The `_.property` iteratee shorthand.
_.findIndex(users, 'active');
// => 2
# static findKey(object, predicateopt) → {string|undefined}
This method is like _.find except that it returns the key of the first
element predicate returns truthy for instead of the element itself.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to inspect. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 1.1.0
Returns the key of the matched element,
else undefined.
Example
var users = {
'barney': { 'age': 36, 'active': true },
'fred': { 'age': 40, 'active': false },
'pebbles': { 'age': 1, 'active': true }
};
_.findKey(users, function(o) { return o.age < 40; });
// => 'barney' (iteration order is not guaranteed)
// The `_.matches` iteratee shorthand.
_.findKey(users, { 'age': 1, 'active': true });
// => 'pebbles'
// The `_.matchesProperty` iteratee shorthand.
_.findKey(users, ['active', false]);
// => 'fred'
// The `_.property` iteratee shorthand.
_.findKey(users, 'active');
// => 'barney'
# static findKey(object, predicateopt) → {string|undefined}
This method is like _.find except that it returns the key of the first
element predicate returns truthy for instead of the element itself.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to inspect. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 1.1.0
Returns the key of the matched element,
else undefined.
Example
var users = {
'barney': { 'age': 36, 'active': true },
'fred': { 'age': 40, 'active': false },
'pebbles': { 'age': 1, 'active': true }
};
_.findKey(users, function(o) { return o.age < 40; });
// => 'barney' (iteration order is not guaranteed)
// The `_.matches` iteratee shorthand.
_.findKey(users, { 'age': 1, 'active': true });
// => 'pebbles'
// The `_.matchesProperty` iteratee shorthand.
_.findKey(users, ['active', false]);
// => 'fred'
// The `_.property` iteratee shorthand.
_.findKey(users, 'active');
// => 'barney'
# static findLastIndex(array, predicateopt, fromIndexopt) → {number}
This method is like _.findIndex except that it iterates over elements
of collection from right to left.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to inspect. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
fromIndex |
number |
<optional> |
array.length-1 | The index to search from. |
- Since:
- 2.0.0
Returns the index of the found element, else -1.
Example
var users = [
{ 'user': 'barney', 'active': true },
{ 'user': 'fred', 'active': false },
{ 'user': 'pebbles', 'active': false }
];
_.findLastIndex(users, function(o) { return o.user == 'pebbles'; });
// => 2
// The `_.matches` iteratee shorthand.
_.findLastIndex(users, { 'user': 'barney', 'active': true });
// => 0
// The `_.matchesProperty` iteratee shorthand.
_.findLastIndex(users, ['active', false]);
// => 2
// The `_.property` iteratee shorthand.
_.findLastIndex(users, 'active');
// => 0
# static findLastIndex(array, predicateopt, fromIndexopt) → {number}
This method is like _.findIndex except that it iterates over elements
of collection from right to left.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to inspect. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
fromIndex |
number |
<optional> |
array.length-1 | The index to search from. |
- Since:
- 2.0.0
Returns the index of the found element, else -1.
Example
var users = [
{ 'user': 'barney', 'active': true },
{ 'user': 'fred', 'active': false },
{ 'user': 'pebbles', 'active': false }
];
_.findLastIndex(users, function(o) { return o.user == 'pebbles'; });
// => 2
// The `_.matches` iteratee shorthand.
_.findLastIndex(users, { 'user': 'barney', 'active': true });
// => 0
// The `_.matchesProperty` iteratee shorthand.
_.findLastIndex(users, ['active', false]);
// => 2
// The `_.property` iteratee shorthand.
_.findLastIndex(users, 'active');
// => 0
# static findLastKey(object, predicateopt) → {string|undefined}
This method is like _.findKey except that it iterates over elements of
a collection in the opposite order.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to inspect. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 2.0.0
Returns the key of the matched element,
else undefined.
Example
var users = {
'barney': { 'age': 36, 'active': true },
'fred': { 'age': 40, 'active': false },
'pebbles': { 'age': 1, 'active': true }
};
_.findLastKey(users, function(o) { return o.age < 40; });
// => returns 'pebbles' assuming `_.findKey` returns 'barney'
// The `_.matches` iteratee shorthand.
_.findLastKey(users, { 'age': 36, 'active': true });
// => 'barney'
// The `_.matchesProperty` iteratee shorthand.
_.findLastKey(users, ['active', false]);
// => 'fred'
// The `_.property` iteratee shorthand.
_.findLastKey(users, 'active');
// => 'pebbles'
# static findLastKey(object, predicateopt) → {string|undefined}
This method is like _.findKey except that it iterates over elements of
a collection in the opposite order.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to inspect. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 2.0.0
Returns the key of the matched element,
else undefined.
Example
var users = {
'barney': { 'age': 36, 'active': true },
'fred': { 'age': 40, 'active': false },
'pebbles': { 'age': 1, 'active': true }
};
_.findLastKey(users, function(o) { return o.age < 40; });
// => returns 'pebbles' assuming `_.findKey` returns 'barney'
// The `_.matches` iteratee shorthand.
_.findLastKey(users, { 'age': 36, 'active': true });
// => 'barney'
// The `_.matchesProperty` iteratee shorthand.
_.findLastKey(users, ['active', false]);
// => 'fred'
// The `_.property` iteratee shorthand.
_.findLastKey(users, 'active');
// => 'pebbles'
# static first(array) → {*}
Gets the first element of array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to query. |
- Since:
- 0.1.0
Returns the first element of array.
Example
_.head([1, 2, 3]);
// => 1
_.head([]);
// => undefined
# static first(array) → {*}
Gets the first element of array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to query. |
- Since:
- 0.1.0
Returns the first element of array.
Example
_.head([1, 2, 3]);
// => 1
_.head([]);
// => undefined
# static first(array) → {*}
Gets the first element of array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to query. |
- Since:
- 0.1.0
Returns the first element of array.
Example
_.head([1, 2, 3]);
// => 1
_.head([]);
// => undefined
# static flatMap(collection, iterateeopt) → {Array}
Creates a flattened array of values by running each element in collection
thru iteratee and flattening the mapped results. The iteratee is invoked
with three arguments: (value, index|key, collection).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 4.0.0
Returns the new flattened array.
Example
function duplicate(n) {
return [n, n];
}
_.flatMap([1, 2], duplicate);
// => [1, 1, 2, 2]
# static flatMap(collection, iterateeopt) → {Array}
Creates a flattened array of values by running each element in collection
thru iteratee and flattening the mapped results. The iteratee is invoked
with three arguments: (value, index|key, collection).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 4.0.0
Returns the new flattened array.
Example
function duplicate(n) {
return [n, n];
}
_.flatMap([1, 2], duplicate);
// => [1, 1, 2, 2]
# static flatMapDeep(collection, iterateeopt) → {Array}
This method is like _.flatMap except that it recursively flattens the
mapped results.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 4.7.0
Returns the new flattened array.
Example
function duplicate(n) {
return [[[n, n]]];
}
_.flatMapDeep([1, 2], duplicate);
// => [1, 1, 2, 2]
# static flatMapDeep(collection, iterateeopt) → {Array}
This method is like _.flatMap except that it recursively flattens the
mapped results.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 4.7.0
Returns the new flattened array.
Example
function duplicate(n) {
return [[[n, n]]];
}
_.flatMapDeep([1, 2], duplicate);
// => [1, 1, 2, 2]
# static flatMapDepth(collection, iterateeopt, depthopt) → {Array}
This method is like _.flatMap except that it recursively flattens the
mapped results up to depth times.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
depth |
number |
<optional> |
1 | The maximum recursion depth. |
- Since:
- 4.7.0
Returns the new flattened array.
Example
function duplicate(n) {
return [[[n, n]]];
}
_.flatMapDepth([1, 2], duplicate, 2);
// => [[1, 1], [2, 2]]
# static flatMapDepth(collection, iterateeopt, depthopt) → {Array}
This method is like _.flatMap except that it recursively flattens the
mapped results up to depth times.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
depth |
number |
<optional> |
1 | The maximum recursion depth. |
- Since:
- 4.7.0
Returns the new flattened array.
Example
function duplicate(n) {
return [[[n, n]]];
}
_.flatMapDepth([1, 2], duplicate, 2);
// => [[1, 1], [2, 2]]
# static flatten(array) → {Array}
Flattens array a single level deep.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to flatten. |
- Since:
- 0.1.0
Returns the new flattened array.
Example
_.flatten([1, [2, [3, [4]], 5]]);
// => [1, 2, [3, [4]], 5]
# static flatten(array) → {Array}
Flattens array a single level deep.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to flatten. |
- Since:
- 0.1.0
Returns the new flattened array.
Example
_.flatten([1, [2, [3, [4]], 5]]);
// => [1, 2, [3, [4]], 5]
# static flatten(array) → {Array}
Flattens array a single level deep.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to flatten. |
- Since:
- 0.1.0
Returns the new flattened array.
Example
_.flatten([1, [2, [3, [4]], 5]]);
// => [1, 2, [3, [4]], 5]
# static flattenDeep(array) → {Array}
Recursively flattens array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to flatten. |
- Since:
- 3.0.0
Returns the new flattened array.
Example
_.flattenDeep([1, [2, [3, [4]], 5]]);
// => [1, 2, 3, 4, 5]
# static flattenDeep(array) → {Array}
Recursively flattens array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to flatten. |
- Since:
- 3.0.0
Returns the new flattened array.
Example
_.flattenDeep([1, [2, [3, [4]], 5]]);
// => [1, 2, 3, 4, 5]
# static flattenDeep(array) → {Array}
Recursively flattens array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to flatten. |
- Since:
- 3.0.0
Returns the new flattened array.
Example
_.flattenDeep([1, [2, [3, [4]], 5]]);
// => [1, 2, 3, 4, 5]
# static flattenDepth(array, depthopt) → {Array}
Recursively flatten array up to depth times.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to flatten. |
||
depth |
number |
<optional> |
1 | The maximum recursion depth. |
- Since:
- 4.4.0
Returns the new flattened array.
Example
var array = [1, [2, [3, [4]], 5]];
_.flattenDepth(array, 1);
// => [1, 2, [3, [4]], 5]
_.flattenDepth(array, 2);
// => [1, 2, 3, [4], 5]
# static flattenDepth(array, depthopt) → {Array}
Recursively flatten array up to depth times.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to flatten. |
||
depth |
number |
<optional> |
1 | The maximum recursion depth. |
- Since:
- 4.4.0
Returns the new flattened array.
Example
var array = [1, [2, [3, [4]], 5]];
_.flattenDepth(array, 1);
// => [1, 2, [3, [4]], 5]
_.flattenDepth(array, 2);
// => [1, 2, 3, [4], 5]
# static flip(func) → {function}
Creates a function that invokes func with arguments reversed.
Parameters:
| Name | Type | Description |
|---|---|---|
func |
function | The function to flip arguments for. |
- Since:
- 4.0.0
Returns the new flipped function.
Example
var flipped = _.flip(function() {
return _.toArray(arguments);
});
flipped('a', 'b', 'c', 'd');
// => ['d', 'c', 'b', 'a']
# static flip(func) → {function}
Creates a function that invokes func with arguments reversed.
Parameters:
| Name | Type | Description |
|---|---|---|
func |
function | The function to flip arguments for. |
- Since:
- 4.0.0
Returns the new flipped function.
Example
var flipped = _.flip(function() {
return _.toArray(arguments);
});
flipped('a', 'b', 'c', 'd');
// => ['d', 'c', 'b', 'a']
# static forIn(object, iterateeopt) → {Object}
Iterates over own and inherited enumerable string keyed properties of an
object and invokes iteratee for each property. The iteratee is invoked
with three arguments: (value, key, object). Iteratee functions may exit
iteration early by explicitly returning false.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.3.0
- See:
Returns object.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.forIn(new Foo, function(value, key) {
console.log(key);
});
// => Logs 'a', 'b', then 'c' (iteration order is not guaranteed).
# static forIn(object, iterateeopt) → {Object}
Iterates over own and inherited enumerable string keyed properties of an
object and invokes iteratee for each property. The iteratee is invoked
with three arguments: (value, key, object). Iteratee functions may exit
iteration early by explicitly returning false.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.3.0
- See:
Returns object.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.forIn(new Foo, function(value, key) {
console.log(key);
});
// => Logs 'a', 'b', then 'c' (iteration order is not guaranteed).
# static forInRight(object, iterateeopt) → {Object}
This method is like _.forIn except that it iterates over properties of
object in the opposite order.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 2.0.0
- See:
Returns object.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.forInRight(new Foo, function(value, key) {
console.log(key);
});
// => Logs 'c', 'b', then 'a' assuming `_.forIn` logs 'a', 'b', then 'c'.
# static forInRight(object, iterateeopt) → {Object}
This method is like _.forIn except that it iterates over properties of
object in the opposite order.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 2.0.0
- See:
Returns object.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.forInRight(new Foo, function(value, key) {
console.log(key);
});
// => Logs 'c', 'b', then 'a' assuming `_.forIn` logs 'a', 'b', then 'c'.
# static forOwn(object, iterateeopt) → {Object}
Iterates over own enumerable string keyed properties of an object and
invokes iteratee for each property. The iteratee is invoked with three
arguments: (value, key, object). Iteratee functions may exit iteration
early by explicitly returning false.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.3.0
- See:
Returns object.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.forOwn(new Foo, function(value, key) {
console.log(key);
});
// => Logs 'a' then 'b' (iteration order is not guaranteed).
# static forOwn(object, iterateeopt) → {Object}
Iterates over own enumerable string keyed properties of an object and
invokes iteratee for each property. The iteratee is invoked with three
arguments: (value, key, object). Iteratee functions may exit iteration
early by explicitly returning false.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.3.0
- See:
Returns object.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.forOwn(new Foo, function(value, key) {
console.log(key);
});
// => Logs 'a' then 'b' (iteration order is not guaranteed).
# static forOwnRight(object, iterateeopt) → {Object}
This method is like _.forOwn except that it iterates over properties of
object in the opposite order.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 2.0.0
- See:
Returns object.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.forOwnRight(new Foo, function(value, key) {
console.log(key);
});
// => Logs 'b' then 'a' assuming `_.forOwn` logs 'a' then 'b'.
# static forOwnRight(object, iterateeopt) → {Object}
This method is like _.forOwn except that it iterates over properties of
object in the opposite order.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 2.0.0
- See:
Returns object.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.forOwnRight(new Foo, function(value, key) {
console.log(key);
});
// => Logs 'b' then 'a' assuming `_.forOwn` logs 'a' then 'b'.
# static fromPairs(pairs) → {Object}
The inverse of _.toPairs; this method returns an object composed
from key-value pairs.
Parameters:
| Name | Type | Description |
|---|---|---|
pairs |
Array | The key-value pairs. |
- Since:
- 4.0.0
Returns the new object.
Example
_.fromPairs([['a', 1], ['b', 2]]);
// => { 'a': 1, 'b': 2 }
# static fromPairs(pairs) → {Object}
The inverse of _.toPairs; this method returns an object composed
from key-value pairs.
Parameters:
| Name | Type | Description |
|---|---|---|
pairs |
Array | The key-value pairs. |
- Since:
- 4.0.0
Returns the new object.
Example
_.fromPairs([['a', 1], ['b', 2]]);
// => { 'a': 1, 'b': 2 }
# static functions(object) → {Array}
Creates an array of function property names from own enumerable properties
of object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to inspect. |
- Since:
- 0.1.0
- See:
Returns the function names.
Example
function Foo() {
this.a = _.constant('a');
this.b = _.constant('b');
}
Foo.prototype.c = _.constant('c');
_.functions(new Foo);
// => ['a', 'b']
# static functions(object) → {Array}
Creates an array of function property names from own enumerable properties
of object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to inspect. |
- Since:
- 0.1.0
- See:
Returns the function names.
Example
function Foo() {
this.a = _.constant('a');
this.b = _.constant('b');
}
Foo.prototype.c = _.constant('c');
_.functions(new Foo);
// => ['a', 'b']
# static functionsIn(object) → {Array}
Creates an array of function property names from own and inherited
enumerable properties of object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to inspect. |
- Since:
- 4.0.0
- See:
Returns the function names.
Example
function Foo() {
this.a = _.constant('a');
this.b = _.constant('b');
}
Foo.prototype.c = _.constant('c');
_.functionsIn(new Foo);
// => ['a', 'b', 'c']
# static functionsIn(object) → {Array}
Creates an array of function property names from own and inherited
enumerable properties of object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to inspect. |
- Since:
- 4.0.0
- See:
Returns the function names.
Example
function Foo() {
this.a = _.constant('a');
this.b = _.constant('b');
}
Foo.prototype.c = _.constant('c');
_.functionsIn(new Foo);
// => ['a', 'b', 'c']
# static get(object, path, defaultValueopt) → {*}
Gets the value at path of object. If the resolved value is
undefined, the defaultValue is returned in its place.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
object |
Object | The object to query. |
|
path |
Array | string | The path of the property to get. |
|
defaultValue |
* |
<optional> |
The value returned for |
- Since:
- 3.7.0
Returns the resolved value.
Example
var object = { 'a': [{ 'b': { 'c': 3 } }] };
_.get(object, 'a[0].b.c');
// => 3
_.get(object, ['a', '0', 'b', 'c']);
// => 3
_.get(object, 'a.b.c', 'default');
// => 'default'
# static get(object, path, defaultValueopt) → {*}
Gets the value at path of object. If the resolved value is
undefined, the defaultValue is returned in its place.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
object |
Object | The object to query. |
|
path |
Array | string | The path of the property to get. |
|
defaultValue |
* |
<optional> |
The value returned for |
- Since:
- 3.7.0
Returns the resolved value.
Example
var object = { 'a': [{ 'b': { 'c': 3 } }] };
_.get(object, 'a[0].b.c');
// => 3
_.get(object, ['a', '0', 'b', 'c']);
// => 3
_.get(object, 'a.b.c', 'default');
// => 'default'
# static getRealtime() → {DashBoardWidget.defaults.realtime|*}
Get realtime
# static has(object, path) → {boolean}
Checks if path is a direct property of object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
path |
Array | string | The path to check. |
- Since:
- 0.1.0
Returns true if path exists, else false.
Example
var object = { 'a': { 'b': 2 } };
var other = _.create({ 'a': _.create({ 'b': 2 }) });
_.has(object, 'a');
// => true
_.has(object, 'a.b');
// => true
_.has(object, ['a', 'b']);
// => true
_.has(other, 'a');
// => false
# static has(object, path) → {boolean}
Checks if path is a direct property of object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
path |
Array | string | The path to check. |
- Since:
- 0.1.0
Returns true if path exists, else false.
Example
var object = { 'a': { 'b': 2 } };
var other = _.create({ 'a': _.create({ 'b': 2 }) });
_.has(object, 'a');
// => true
_.has(object, 'a.b');
// => true
_.has(object, ['a', 'b']);
// => true
_.has(other, 'a');
// => false
# static has(object, path) → {boolean}
Checks if path is a direct property of object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
path |
Array | string | The path to check. |
- Since:
- 0.1.0
Returns true if path exists, else false.
Example
var object = { 'a': { 'b': 2 } };
var other = _.create({ 'a': _.create({ 'b': 2 }) });
_.has(object, 'a');
// => true
_.has(object, 'a.b');
// => true
_.has(object, ['a', 'b']);
// => true
_.has(other, 'a');
// => false
# static hasIn(object, path) → {boolean}
Checks if path is a direct or inherited property of object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
path |
Array | string | The path to check. |
- Since:
- 4.0.0
Returns true if path exists, else false.
Example
var object = _.create({ 'a': _.create({ 'b': 2 }) });
_.hasIn(object, 'a');
// => true
_.hasIn(object, 'a.b');
// => true
_.hasIn(object, ['a', 'b']);
// => true
_.hasIn(object, 'b');
// => false
# static hasIn(object, path) → {boolean}
Checks if path is a direct or inherited property of object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
path |
Array | string | The path to check. |
- Since:
- 4.0.0
Returns true if path exists, else false.
Example
var object = _.create({ 'a': _.create({ 'b': 2 }) });
_.hasIn(object, 'a');
// => true
_.hasIn(object, 'a.b');
// => true
_.hasIn(object, ['a', 'b']);
// => true
_.hasIn(object, 'b');
// => false
# static identity(value) → {*}
This method returns the first argument it receives.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | Any value. |
- Since:
- 0.1.0
Returns value.
Example
var object = { 'a': 1 };
console.log(_.identity(object) === object);
// => true
# static identity(value) → {*}
This method returns the first argument it receives.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | Any value. |
- Since:
- 0.1.0
Returns value.
Example
var object = { 'a': 1 };
console.log(_.identity(object) === object);
// => true
# static identity(value) → {*}
This method returns the first argument it receives.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | Any value. |
- Since:
- 0.1.0
Returns value.
Example
var object = { 'a': 1 };
console.log(_.identity(object) === object);
// => true
# static includes(collection, value, fromIndexopt) → {boolean}
Checks if value is in collection. If collection is a string, it's
checked for a substring of value, otherwise
SameValueZero
is used for equality comparisons. If fromIndex is negative, it's used as
the offset from the end of collection.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | string | The collection to inspect. |
||
value |
* | The value to search for. |
||
fromIndex |
number |
<optional> |
0 | The index to search from. |
- Since:
- 0.1.0
Returns true if value is found, else false.
Example
_.includes([1, 2, 3], 1);
// => true
_.includes([1, 2, 3], 1, 2);
// => false
_.includes({ 'a': 1, 'b': 2 }, 1);
// => true
_.includes('abcd', 'bc');
// => true
# static includes(collection, value, fromIndexopt) → {boolean}
Checks if value is in collection. If collection is a string, it's
checked for a substring of value, otherwise
SameValueZero
is used for equality comparisons. If fromIndex is negative, it's used as
the offset from the end of collection.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | string | The collection to inspect. |
||
value |
* | The value to search for. |
||
fromIndex |
number |
<optional> |
0 | The index to search from. |
- Since:
- 0.1.0
Returns true if value is found, else false.
Example
_.includes([1, 2, 3], 1);
// => true
_.includes([1, 2, 3], 1, 2);
// => false
_.includes({ 'a': 1, 'b': 2 }, 1);
// => true
_.includes('abcd', 'bc');
// => true
# static indexOf(array, value, fromIndexopt) → {number}
Gets the index at which the first occurrence of value is found in array
using SameValueZero
for equality comparisons. If fromIndex is negative, it's used as the
offset from the end of array.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to inspect. |
||
value |
* | The value to search for. |
||
fromIndex |
number |
<optional> |
0 | The index to search from. |
- Since:
- 0.1.0
Returns the index of the matched value, else -1.
Example
_.indexOf([1, 2, 1, 2], 2);
// => 1
// Search from the `fromIndex`.
_.indexOf([1, 2, 1, 2], 2, 2);
// => 3
# static indexOf(array, value, fromIndexopt) → {number}
Gets the index at which the first occurrence of value is found in array
using SameValueZero
for equality comparisons. If fromIndex is negative, it's used as the
offset from the end of array.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to inspect. |
||
value |
* | The value to search for. |
||
fromIndex |
number |
<optional> |
0 | The index to search from. |
- Since:
- 0.1.0
Returns the index of the matched value, else -1.
Example
_.indexOf([1, 2, 1, 2], 2);
// => 1
// Search from the `fromIndex`.
_.indexOf([1, 2, 1, 2], 2, 2);
// => 3
# static indexOf(array, value, fromIndexopt) → {number}
Gets the index at which the first occurrence of value is found in array
using SameValueZero
for equality comparisons. If fromIndex is negative, it's used as the
offset from the end of array.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to inspect. |
||
value |
* | The value to search for. |
||
fromIndex |
number |
<optional> |
0 | The index to search from. |
- Since:
- 0.1.0
Returns the index of the matched value, else -1.
Example
_.indexOf([1, 2, 1, 2], 2);
// => 1
// Search from the `fromIndex`.
_.indexOf([1, 2, 1, 2], 2, 2);
// => 3
# static initial(array) → {Array}
Gets all but the last element of array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to query. |
- Since:
- 0.1.0
Returns the slice of array.
Example
_.initial([1, 2, 3]);
// => [1, 2]
# static initial(array) → {Array}
Gets all but the last element of array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to query. |
- Since:
- 0.1.0
Returns the slice of array.
Example
_.initial([1, 2, 3]);
// => [1, 2]
# static inRange(number, startopt, end) → {boolean}
Checks if n is between start and up to, but not including, end. If
end is not specified, it's set to start with start then set to 0.
If start is greater than end the params are swapped to support
negative ranges.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
number |
number | The number to check. |
||
start |
number |
<optional> |
0 | The start of the range. |
end |
number | The end of the range. |
- Since:
- 3.3.0
- See:
-
- _.range, _.rangeRight
Returns true if number is in the range, else false.
Example
_.inRange(3, 2, 4);
// => true
_.inRange(4, 8);
// => true
_.inRange(4, 2);
// => false
_.inRange(2, 2);
// => false
_.inRange(1.2, 2);
// => true
_.inRange(5.2, 4);
// => false
_.inRange(-3, -2, -6);
// => true
# static inRange(number, startopt, end) → {boolean}
Checks if n is between start and up to, but not including, end. If
end is not specified, it's set to start with start then set to 0.
If start is greater than end the params are swapped to support
negative ranges.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
number |
number | The number to check. |
||
start |
number |
<optional> |
0 | The start of the range. |
end |
number | The end of the range. |
- Since:
- 3.3.0
- See:
-
- _.range, _.rangeRight
Returns true if number is in the range, else false.
Example
_.inRange(3, 2, 4);
// => true
_.inRange(4, 8);
// => true
_.inRange(4, 2);
// => false
_.inRange(2, 2);
// => false
_.inRange(1.2, 2);
// => true
_.inRange(5.2, 4);
// => false
_.inRange(-3, -2, -6);
// => true
# static isArrayLike(value) → {boolean}
Checks if value is array-like. A value is considered array-like if it's
not a function and has a value.length that's an integer greater than or
equal to 0 and less than or equal to Number.MAX_SAFE_INTEGER.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is array-like, else false.
Example
_.isArrayLike([1, 2, 3]);
// => true
_.isArrayLike(document.body.children);
// => true
_.isArrayLike('abc');
// => true
_.isArrayLike(_.noop);
// => false
# static isArrayLike(value) → {boolean}
Checks if value is array-like. A value is considered array-like if it's
not a function and has a value.length that's an integer greater than or
equal to 0 and less than or equal to Number.MAX_SAFE_INTEGER.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is array-like, else false.
Example
_.isArrayLike([1, 2, 3]);
// => true
_.isArrayLike(document.body.children);
// => true
_.isArrayLike('abc');
// => true
_.isArrayLike(_.noop);
// => false
# static isArrayLike(value) → {boolean}
Checks if value is array-like. A value is considered array-like if it's
not a function and has a value.length that's an integer greater than or
equal to 0 and less than or equal to Number.MAX_SAFE_INTEGER.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is array-like, else false.
Example
_.isArrayLike([1, 2, 3]);
// => true
_.isArrayLike(document.body.children);
// => true
_.isArrayLike('abc');
// => true
_.isArrayLike(_.noop);
// => false
# static isArrayLikeObject(value) → {boolean}
This method is like _.isArrayLike except that it also checks if value
is an object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
View Source node_modules/lodash/isArrayLikeObject.js, line 29
Returns true if value is an array-like object,
else false.
Example
_.isArrayLikeObject([1, 2, 3]);
// => true
_.isArrayLikeObject(document.body.children);
// => true
_.isArrayLikeObject('abc');
// => false
_.isArrayLikeObject(_.noop);
// => false
# static isArrayLikeObject(value) → {boolean}
This method is like _.isArrayLike except that it also checks if value
is an object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is an array-like object,
else false.
Example
_.isArrayLikeObject([1, 2, 3]);
// => true
_.isArrayLikeObject(document.body.children);
// => true
_.isArrayLikeObject('abc');
// => false
_.isArrayLikeObject(_.noop);
// => false
# static isBoolean(value) → {boolean}
Checks if value is classified as a boolean primitive or object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a boolean, else false.
Example
_.isBoolean(false);
// => true
_.isBoolean(null);
// => false
# static isBoolean(value) → {boolean}
Checks if value is classified as a boolean primitive or object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a boolean, else false.
Example
_.isBoolean(false);
// => true
_.isBoolean(null);
// => false
# static isBoolean(value) → {boolean}
Checks if value is classified as a boolean primitive or object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a boolean, else false.
Example
_.isBoolean(false);
// => true
_.isBoolean(null);
// => false
# static isElement(value) → {boolean}
Checks if value is likely a DOM element.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a DOM element, else false.
Example
_.isElement(document.body);
// => true
_.isElement('<body>');
// => false
# static isElement(value) → {boolean}
Checks if value is likely a DOM element.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a DOM element, else false.
Example
_.isElement(document.body);
// => true
_.isElement('<body>');
// => false
# static isEmpty(value) → {boolean}
Checks if value is an empty object, collection, map, or set.
Objects are considered empty if they have no own enumerable string keyed properties.
Array-like values such as arguments objects, arrays, buffers, strings, or
jQuery-like collections are considered empty if they have a length of 0.
Similarly, maps and sets are considered empty if they have a size of 0.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is empty, else false.
Example
_.isEmpty(null);
// => true
_.isEmpty(true);
// => true
_.isEmpty(1);
// => true
_.isEmpty([1, 2, 3]);
// => false
_.isEmpty({ 'a': 1 });
// => false
# static isEmpty(value) → {boolean}
Checks if value is an empty object, collection, map, or set.
Objects are considered empty if they have no own enumerable string keyed properties.
Array-like values such as arguments objects, arrays, buffers, strings, or
jQuery-like collections are considered empty if they have a length of 0.
Similarly, maps and sets are considered empty if they have a size of 0.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is empty, else false.
Example
_.isEmpty(null);
// => true
_.isEmpty(true);
// => true
_.isEmpty(1);
// => true
_.isEmpty([1, 2, 3]);
// => false
_.isEmpty({ 'a': 1 });
// => false
# static isEmpty(value) → {boolean}
Checks if value is an empty object, collection, map, or set.
Objects are considered empty if they have no own enumerable string keyed properties.
Array-like values such as arguments objects, arrays, buffers, strings, or
jQuery-like collections are considered empty if they have a length of 0.
Similarly, maps and sets are considered empty if they have a size of 0.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is empty, else false.
Example
_.isEmpty(null);
// => true
_.isEmpty(true);
// => true
_.isEmpty(1);
// => true
_.isEmpty([1, 2, 3]);
// => false
_.isEmpty({ 'a': 1 });
// => false
# static isEqual(value, other) → {boolean}
Performs a deep comparison between two values to determine if they are equivalent.
Note: This method supports comparing arrays, array buffers, booleans,
date objects, error objects, maps, numbers, Object objects, regexes,
sets, strings, symbols, and typed arrays. Object objects are compared
by their own, not inherited, enumerable properties. Functions and DOM
nodes are compared by strict equality, i.e. ===.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to compare. |
other |
* | The other value to compare. |
- Since:
- 0.1.0
Returns true if the values are equivalent, else false.
Example
var object = { 'a': 1 };
var other = { 'a': 1 };
_.isEqual(object, other);
// => true
object === other;
// => false
# static isEqual(value, other) → {boolean}
Performs a deep comparison between two values to determine if they are equivalent.
Note: This method supports comparing arrays, array buffers, booleans,
date objects, error objects, maps, numbers, Object objects, regexes,
sets, strings, symbols, and typed arrays. Object objects are compared
by their own, not inherited, enumerable properties. Functions and DOM
nodes are compared by strict equality, i.e. ===.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to compare. |
other |
* | The other value to compare. |
- Since:
- 0.1.0
Returns true if the values are equivalent, else false.
Example
var object = { 'a': 1 };
var other = { 'a': 1 };
_.isEqual(object, other);
// => true
object === other;
// => false
# static isEqual(value, other) → {boolean}
Performs a deep comparison between two values to determine if they are equivalent.
Note: This method supports comparing arrays, array buffers, booleans,
date objects, error objects, maps, numbers, Object objects, regexes,
sets, strings, symbols, and typed arrays. Object objects are compared
by their own, not inherited, enumerable properties. Functions and DOM
nodes are compared by strict equality, i.e. ===.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to compare. |
other |
* | The other value to compare. |
- Since:
- 0.1.0
Returns true if the values are equivalent, else false.
Example
var object = { 'a': 1 };
var other = { 'a': 1 };
_.isEqual(object, other);
// => true
object === other;
// => false
# static isEqualWith(value, other, customizeropt) → {boolean}
This method is like _.isEqual except that it accepts customizer which
is invoked to compare values. If customizer returns undefined, comparisons
are handled by the method instead. The customizer is invoked with up to
six arguments: (objValue, othValue [, index|key, object, other, stack]).
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
value |
* | The value to compare. |
|
other |
* | The other value to compare. |
|
customizer |
function |
<optional> |
The function to customize comparisons. |
- Since:
- 4.0.0
Returns true if the values are equivalent, else false.
Example
function isGreeting(value) {
return /^h(?:i|ello)$/.test(value);
}
function customizer(objValue, othValue) {
if (isGreeting(objValue) && isGreeting(othValue)) {
return true;
}
}
var array = ['hello', 'goodbye'];
var other = ['hi', 'goodbye'];
_.isEqualWith(array, other, customizer);
// => true
# static isEqualWith(value, other, customizeropt) → {boolean}
This method is like _.isEqual except that it accepts customizer which
is invoked to compare values. If customizer returns undefined, comparisons
are handled by the method instead. The customizer is invoked with up to
six arguments: (objValue, othValue [, index|key, object, other, stack]).
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
value |
* | The value to compare. |
|
other |
* | The other value to compare. |
|
customizer |
function |
<optional> |
The function to customize comparisons. |
- Since:
- 4.0.0
Returns true if the values are equivalent, else false.
Example
function isGreeting(value) {
return /^h(?:i|ello)$/.test(value);
}
function customizer(objValue, othValue) {
if (isGreeting(objValue) && isGreeting(othValue)) {
return true;
}
}
var array = ['hello', 'goodbye'];
var other = ['hi', 'goodbye'];
_.isEqualWith(array, other, customizer);
// => true
# static isError(value) → {boolean}
Checks if value is an Error, EvalError, RangeError, ReferenceError,
SyntaxError, TypeError, or URIError object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 3.0.0
Returns true if value is an error object, else false.
Example
_.isError(new Error);
// => true
_.isError(Error);
// => false
# static isError(value) → {boolean}
Checks if value is an Error, EvalError, RangeError, ReferenceError,
SyntaxError, TypeError, or URIError object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 3.0.0
Returns true if value is an error object, else false.
Example
_.isError(new Error);
// => true
_.isError(Error);
// => false
# static isFinite(value) → {boolean}
Checks if value is a finite primitive number.
Note: This method is based on
Number.isFinite.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a finite number, else false.
Example
_.isFinite(3);
// => true
_.isFinite(Number.MIN_VALUE);
// => true
_.isFinite(Infinity);
// => false
_.isFinite('3');
// => false
# static isFinite(value) → {boolean}
Checks if value is a finite primitive number.
Note: This method is based on
Number.isFinite.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a finite number, else false.
Example
_.isFinite(3);
// => true
_.isFinite(Number.MIN_VALUE);
// => true
_.isFinite(Infinity);
// => false
_.isFinite('3');
// => false
# static isFinite(value) → {boolean}
Checks if value is a finite primitive number.
Note: This method is based on
Number.isFinite.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a finite number, else false.
Example
_.isFinite(3);
// => true
_.isFinite(Number.MIN_VALUE);
// => true
_.isFinite(Infinity);
// => false
_.isFinite('3');
// => false
# static isFunction(value) → {boolean}
Checks if value is classified as a Function object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a function, else false.
Example
_.isFunction(_);
// => true
_.isFunction(/abc/);
// => false
# static isFunction(value) → {boolean}
Checks if value is classified as a Function object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a function, else false.
Example
_.isFunction(_);
// => true
_.isFunction(/abc/);
// => false
# static isFunction(value) → {boolean}
Checks if value is classified as a Function object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a function, else false.
Example
_.isFunction(_);
// => true
_.isFunction(/abc/);
// => false
# static isInteger(value) → {boolean}
Checks if value is an integer.
Note: This method is based on
Number.isInteger.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is an integer, else false.
Example
_.isInteger(3);
// => true
_.isInteger(Number.MIN_VALUE);
// => false
_.isInteger(Infinity);
// => false
_.isInteger('3');
// => false
# static isInteger(value) → {boolean}
Checks if value is an integer.
Note: This method is based on
Number.isInteger.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is an integer, else false.
Example
_.isInteger(3);
// => true
_.isInteger(Number.MIN_VALUE);
// => false
_.isInteger(Infinity);
// => false
_.isInteger('3');
// => false
# static isLength(value) → {boolean}
Checks if value is a valid array-like length.
Note: This method is loosely based on
ToLength.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is a valid length, else false.
Example
_.isLength(3);
// => true
_.isLength(Number.MIN_VALUE);
// => false
_.isLength(Infinity);
// => false
_.isLength('3');
// => false
# static isLength(value) → {boolean}
Checks if value is a valid array-like length.
Note: This method is loosely based on
ToLength.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is a valid length, else false.
Example
_.isLength(3);
// => true
_.isLength(Number.MIN_VALUE);
// => false
_.isLength(Infinity);
// => false
_.isLength('3');
// => false
# static isLength(value) → {boolean}
Checks if value is a valid array-like length.
Note: This method is loosely based on
ToLength.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is a valid length, else false.
Example
_.isLength(3);
// => true
_.isLength(Number.MIN_VALUE);
// => false
_.isLength(Infinity);
// => false
_.isLength('3');
// => false
# static isMatch(object, source) → {boolean}
Performs a partial deep comparison between object and source to
determine if object contains equivalent property values.
Note: This method is equivalent to _.matches when source is
partially applied.
Partial comparisons will match empty array and empty object source
values against any array or object value, respectively. See _.isEqual
for a list of supported value comparisons.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to inspect. |
source |
Object | The object of property values to match. |
- Since:
- 3.0.0
Returns true if object is a match, else false.
Example
var object = { 'a': 1, 'b': 2 };
_.isMatch(object, { 'b': 2 });
// => true
_.isMatch(object, { 'b': 1 });
// => false
# static isMatch(object, source) → {boolean}
Performs a partial deep comparison between object and source to
determine if object contains equivalent property values.
Note: This method is equivalent to _.matches when source is
partially applied.
Partial comparisons will match empty array and empty object source
values against any array or object value, respectively. See _.isEqual
for a list of supported value comparisons.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to inspect. |
source |
Object | The object of property values to match. |
- Since:
- 3.0.0
Returns true if object is a match, else false.
Example
var object = { 'a': 1, 'b': 2 };
_.isMatch(object, { 'b': 2 });
// => true
_.isMatch(object, { 'b': 1 });
// => false
# static isMatchWith(object, source, customizeropt) → {boolean}
This method is like _.isMatch except that it accepts customizer which
is invoked to compare values. If customizer returns undefined, comparisons
are handled by the method instead. The customizer is invoked with five
arguments: (objValue, srcValue, index|key, object, source).
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
object |
Object | The object to inspect. |
|
source |
Object | The object of property values to match. |
|
customizer |
function |
<optional> |
The function to customize comparisons. |
- Since:
- 4.0.0
Returns true if object is a match, else false.
Example
function isGreeting(value) {
return /^h(?:i|ello)$/.test(value);
}
function customizer(objValue, srcValue) {
if (isGreeting(objValue) && isGreeting(srcValue)) {
return true;
}
}
var object = { 'greeting': 'hello' };
var source = { 'greeting': 'hi' };
_.isMatchWith(object, source, customizer);
// => true
# static isMatchWith(object, source, customizeropt) → {boolean}
This method is like _.isMatch except that it accepts customizer which
is invoked to compare values. If customizer returns undefined, comparisons
are handled by the method instead. The customizer is invoked with five
arguments: (objValue, srcValue, index|key, object, source).
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
object |
Object | The object to inspect. |
|
source |
Object | The object of property values to match. |
|
customizer |
function |
<optional> |
The function to customize comparisons. |
- Since:
- 4.0.0
Returns true if object is a match, else false.
Example
function isGreeting(value) {
return /^h(?:i|ello)$/.test(value);
}
function customizer(objValue, srcValue) {
if (isGreeting(objValue) && isGreeting(srcValue)) {
return true;
}
}
var object = { 'greeting': 'hello' };
var source = { 'greeting': 'hi' };
_.isMatchWith(object, source, customizer);
// => true
# static isNaN(value) → {boolean}
Checks if value is NaN.
Note: This method is based on
Number.isNaN and is not the same as
global isNaN which returns true for
undefined and other non-number values.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is NaN, else false.
Example
_.isNaN(NaN);
// => true
_.isNaN(new Number(NaN));
// => true
isNaN(undefined);
// => true
_.isNaN(undefined);
// => false
# static isNaN(value) → {boolean}
Checks if value is NaN.
Note: This method is based on
Number.isNaN and is not the same as
global isNaN which returns true for
undefined and other non-number values.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is NaN, else false.
Example
_.isNaN(NaN);
// => true
_.isNaN(new Number(NaN));
// => true
isNaN(undefined);
// => true
_.isNaN(undefined);
// => false
# static isNaN(value) → {boolean}
Checks if value is NaN.
Note: This method is based on
Number.isNaN and is not the same as
global isNaN which returns true for
undefined and other non-number values.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is NaN, else false.
Example
_.isNaN(NaN);
// => true
_.isNaN(new Number(NaN));
// => true
isNaN(undefined);
// => true
_.isNaN(undefined);
// => false
# static isNative(value) → {boolean}
Checks if value is a pristine native function.
Note: This method can't reliably detect native functions in the presence of the core-js package because core-js circumvents this kind of detection. Despite multiple requests, the core-js maintainer has made it clear: any attempt to fix the detection will be obstructed. As a result, we're left with little choice but to throw an error. Unfortunately, this also affects packages, like babel-polyfill, which rely on core-js.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 3.0.0
Returns true if value is a native function,
else false.
Example
_.isNative(Array.prototype.push);
// => true
_.isNative(_);
// => false
# static isNative(value) → {boolean}
Checks if value is a pristine native function.
Note: This method can't reliably detect native functions in the presence of the core-js package because core-js circumvents this kind of detection. Despite multiple requests, the core-js maintainer has made it clear: any attempt to fix the detection will be obstructed. As a result, we're left with little choice but to throw an error. Unfortunately, this also affects packages, like babel-polyfill, which rely on core-js.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 3.0.0
Returns true if value is a native function,
else false.
Example
_.isNative(Array.prototype.push);
// => true
_.isNative(_);
// => false
# static isNil(value) → {boolean}
Checks if value is null or undefined.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is nullish, else false.
Example
_.isNil(null);
// => true
_.isNil(void 0);
// => true
_.isNil(NaN);
// => false
# static isNil(value) → {boolean}
Checks if value is null or undefined.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is nullish, else false.
Example
_.isNil(null);
// => true
_.isNil(void 0);
// => true
_.isNil(NaN);
// => false
# static isNull(value) → {boolean}
Checks if value is null.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is null, else false.
Example
_.isNull(null);
// => true
_.isNull(void 0);
// => false
# static isNull(value) → {boolean}
Checks if value is null.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is null, else false.
Example
_.isNull(null);
// => true
_.isNull(void 0);
// => false
# static isNull(value) → {boolean}
Checks if value is null.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is null, else false.
Example
_.isNull(null);
// => true
_.isNull(void 0);
// => false
# static isNumber(value) → {boolean}
Checks if value is classified as a Number primitive or object.
Note: To exclude Infinity, -Infinity, and NaN, which are
classified as numbers, use the _.isFinite method.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a number, else false.
Example
_.isNumber(3);
// => true
_.isNumber(Number.MIN_VALUE);
// => true
_.isNumber(Infinity);
// => true
_.isNumber('3');
// => false
# static isNumber(value) → {boolean}
Checks if value is classified as a Number primitive or object.
Note: To exclude Infinity, -Infinity, and NaN, which are
classified as numbers, use the _.isFinite method.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a number, else false.
Example
_.isNumber(3);
// => true
_.isNumber(Number.MIN_VALUE);
// => true
_.isNumber(Infinity);
// => true
_.isNumber('3');
// => false
# static isNumber(value) → {boolean}
Checks if value is classified as a Number primitive or object.
Note: To exclude Infinity, -Infinity, and NaN, which are
classified as numbers, use the _.isFinite method.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a number, else false.
Example
_.isNumber(3);
// => true
_.isNumber(Number.MIN_VALUE);
// => true
_.isNumber(Infinity);
// => true
_.isNumber('3');
// => false
# static isObject(value) → {boolean}
Checks if value is the
language type
of Object. (e.g. arrays, functions, objects, regexes, new Number(0), and new String(''))
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is an object, else false.
Example
_.isObject({});
// => true
_.isObject([1, 2, 3]);
// => true
_.isObject(_.noop);
// => true
_.isObject(null);
// => false
# static isObject(value) → {boolean}
Checks if value is the
language type
of Object. (e.g. arrays, functions, objects, regexes, new Number(0), and new String(''))
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is an object, else false.
Example
_.isObject({});
// => true
_.isObject([1, 2, 3]);
// => true
_.isObject(_.noop);
// => true
_.isObject(null);
// => false
# static isObject(value) → {boolean}
Checks if value is the
language type
of Object. (e.g. arrays, functions, objects, regexes, new Number(0), and new String(''))
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is an object, else false.
Example
_.isObject({});
// => true
_.isObject([1, 2, 3]);
// => true
_.isObject(_.noop);
// => true
_.isObject(null);
// => false
# static isObjectLike(value) → {boolean}
Checks if value is object-like. A value is object-like if it's not null
and has a typeof result of "object".
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is object-like, else false.
Example
_.isObjectLike({});
// => true
_.isObjectLike([1, 2, 3]);
// => true
_.isObjectLike(_.noop);
// => false
_.isObjectLike(null);
// => false
# static isObjectLike(value) → {boolean}
Checks if value is object-like. A value is object-like if it's not null
and has a typeof result of "object".
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is object-like, else false.
Example
_.isObjectLike({});
// => true
_.isObjectLike([1, 2, 3]);
// => true
_.isObjectLike(_.noop);
// => false
_.isObjectLike(null);
// => false
# static isObjectLike(value) → {boolean}
Checks if value is object-like. A value is object-like if it's not null
and has a typeof result of "object".
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is object-like, else false.
Example
_.isObjectLike({});
// => true
_.isObjectLike([1, 2, 3]);
// => true
_.isObjectLike(_.noop);
// => false
_.isObjectLike(null);
// => false
# static isPlainObject(value) → {boolean}
Checks if value is a plain object, that is, an object created by the
Object constructor or one with a [[Prototype]] of null.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.8.0
Returns true if value is a plain object, else false.
Example
function Foo() {
this.a = 1;
}
_.isPlainObject(new Foo);
// => false
_.isPlainObject([1, 2, 3]);
// => false
_.isPlainObject({ 'x': 0, 'y': 0 });
// => true
_.isPlainObject(Object.create(null));
// => true
# static isPlainObject(value) → {boolean}
Checks if value is a plain object, that is, an object created by the
Object constructor or one with a [[Prototype]] of null.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.8.0
Returns true if value is a plain object, else false.
Example
function Foo() {
this.a = 1;
}
_.isPlainObject(new Foo);
// => false
_.isPlainObject([1, 2, 3]);
// => false
_.isPlainObject({ 'x': 0, 'y': 0 });
// => true
_.isPlainObject(Object.create(null));
// => true
# static isSafeInteger(value) → {boolean}
Checks if value is a safe integer. An integer is safe if it's an IEEE-754
double precision number which isn't the result of a rounded unsafe integer.
Note: This method is based on
Number.isSafeInteger.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is a safe integer, else false.
Example
_.isSafeInteger(3);
// => true
_.isSafeInteger(Number.MIN_VALUE);
// => false
_.isSafeInteger(Infinity);
// => false
_.isSafeInteger('3');
// => false
# static isSafeInteger(value) → {boolean}
Checks if value is a safe integer. An integer is safe if it's an IEEE-754
double precision number which isn't the result of a rounded unsafe integer.
Note: This method is based on
Number.isSafeInteger.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is a safe integer, else false.
Example
_.isSafeInteger(3);
// => true
_.isSafeInteger(Number.MIN_VALUE);
// => false
_.isSafeInteger(Infinity);
// => false
_.isSafeInteger('3');
// => false
# static isString(value) → {boolean}
Checks if value is classified as a String primitive or object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a string, else false.
Example
_.isString('abc');
// => true
_.isString(1);
// => false
# static isString(value) → {boolean}
Checks if value is classified as a String primitive or object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a string, else false.
Example
_.isString('abc');
// => true
_.isString(1);
// => false
# static isString(value) → {boolean}
Checks if value is classified as a String primitive or object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is a string, else false.
Example
_.isString('abc');
// => true
_.isString(1);
// => false
# static isSymbol(value) → {boolean}
Checks if value is classified as a Symbol primitive or object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is a symbol, else false.
Example
_.isSymbol(Symbol.iterator);
// => true
_.isSymbol('abc');
// => false
# static isSymbol(value) → {boolean}
Checks if value is classified as a Symbol primitive or object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.0.0
Returns true if value is a symbol, else false.
Example
_.isSymbol(Symbol.iterator);
// => true
_.isSymbol('abc');
// => false
# static isUndefined(value) → {boolean}
Checks if value is undefined.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is undefined, else false.
Example
_.isUndefined(void 0);
// => true
_.isUndefined(null);
// => false
# static isUndefined(value) → {boolean}
Checks if value is undefined.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is undefined, else false.
Example
_.isUndefined(void 0);
// => true
_.isUndefined(null);
// => false
# static isUndefined(value) → {boolean}
Checks if value is undefined.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 0.1.0
Returns true if value is undefined, else false.
Example
_.isUndefined(void 0);
// => true
_.isUndefined(null);
// => false
# static isWeakMap(value) → {boolean}
Checks if value is classified as a WeakMap object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.3.0
Returns true if value is a weak map, else false.
Example
_.isWeakMap(new WeakMap);
// => true
_.isWeakMap(new Map);
// => false
# static isWeakMap(value) → {boolean}
Checks if value is classified as a WeakMap object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.3.0
Returns true if value is a weak map, else false.
Example
_.isWeakMap(new WeakMap);
// => true
_.isWeakMap(new Map);
// => false
# static isWeakSet(value) → {boolean}
Checks if value is classified as a WeakSet object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.3.0
Returns true if value is a weak set, else false.
Example
_.isWeakSet(new WeakSet);
// => true
_.isWeakSet(new Set);
// => false
# static isWeakSet(value) → {boolean}
Checks if value is classified as a WeakSet object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to check. |
- Since:
- 4.3.0
Returns true if value is a weak set, else false.
Example
_.isWeakSet(new WeakSet);
// => true
_.isWeakSet(new Set);
// => false
# static iteratee(funcopt) → {function}
Creates a function that invokes func with the arguments of the created
function. If func is a property name, the created function returns the
property value for a given element. If func is an array or object, the
created function returns true for elements that contain the equivalent
source properties, otherwise it returns false.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
* |
<optional> |
_.identity | The value to convert to a callback. |
- Since:
- 4.0.0
Returns the callback.
Example
var users = [
{ 'user': 'barney', 'age': 36, 'active': true },
{ 'user': 'fred', 'age': 40, 'active': false }
];
// The `_.matches` iteratee shorthand.
_.filter(users, _.iteratee({ 'user': 'barney', 'active': true }));
// => [{ 'user': 'barney', 'age': 36, 'active': true }]
// The `_.matchesProperty` iteratee shorthand.
_.filter(users, _.iteratee(['user', 'fred']));
// => [{ 'user': 'fred', 'age': 40 }]
// The `_.property` iteratee shorthand.
_.map(users, _.iteratee('user'));
// => ['barney', 'fred']
// Create custom iteratee shorthands.
_.iteratee = _.wrap(_.iteratee, function(iteratee, func) {
return !_.isRegExp(func) ? iteratee(func) : function(string) {
return func.test(string);
};
});
_.filter(['abc', 'def'], /ef/);
// => ['def']
# static iteratee(funcopt) → {function}
Creates a function that invokes func with the arguments of the created
function. If func is a property name, the created function returns the
property value for a given element. If func is an array or object, the
created function returns true for elements that contain the equivalent
source properties, otherwise it returns false.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
* |
<optional> |
_.identity | The value to convert to a callback. |
- Since:
- 4.0.0
Returns the callback.
Example
var users = [
{ 'user': 'barney', 'age': 36, 'active': true },
{ 'user': 'fred', 'age': 40, 'active': false }
];
// The `_.matches` iteratee shorthand.
_.filter(users, _.iteratee({ 'user': 'barney', 'active': true }));
// => [{ 'user': 'barney', 'age': 36, 'active': true }]
// The `_.matchesProperty` iteratee shorthand.
_.filter(users, _.iteratee(['user', 'fred']));
// => [{ 'user': 'fred', 'age': 40 }]
// The `_.property` iteratee shorthand.
_.map(users, _.iteratee('user'));
// => ['barney', 'fred']
// Create custom iteratee shorthands.
_.iteratee = _.wrap(_.iteratee, function(iteratee, func) {
return !_.isRegExp(func) ? iteratee(func) : function(string) {
return func.test(string);
};
});
_.filter(['abc', 'def'], /ef/);
// => ['def']
# static join(array, separatoropt) → {string}
Converts all elements in array into a string separated by separator.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to convert. |
||
separator |
string |
<optional> |
',' | The element separator. |
- Since:
- 4.0.0
Returns the joined string.
Example
_.join(['a', 'b', 'c'], '~');
// => 'a~b~c'
# static join(array, separatoropt) → {string}
Converts all elements in array into a string separated by separator.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to convert. |
||
separator |
string |
<optional> |
',' | The element separator. |
- Since:
- 4.0.0
Returns the joined string.
Example
_.join(['a', 'b', 'c'], '~');
// => 'a~b~c'
# static keys(object) → {Array}
Creates an array of the own enumerable property names of object.
Note: Non-object values are coerced to objects. See the ES spec for more details.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
- Since:
- 0.1.0
Returns the array of property names.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.keys(new Foo);
// => ['a', 'b'] (iteration order is not guaranteed)
_.keys('hi');
// => ['0', '1']
# static keys(object) → {Array}
Creates an array of the own enumerable property names of object.
Note: Non-object values are coerced to objects. See the ES spec for more details.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
- Since:
- 0.1.0
Returns the array of property names.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.keys(new Foo);
// => ['a', 'b'] (iteration order is not guaranteed)
_.keys('hi');
// => ['0', '1']
# static keysIn(object) → {Array}
Creates an array of the own and inherited enumerable property names of object.
Note: Non-object values are coerced to objects.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
- Since:
- 3.0.0
Returns the array of property names.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.keysIn(new Foo);
// => ['a', 'b', 'c'] (iteration order is not guaranteed)
# static keysIn(object) → {Array}
Creates an array of the own and inherited enumerable property names of object.
Note: Non-object values are coerced to objects.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
- Since:
- 3.0.0
Returns the array of property names.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.keysIn(new Foo);
// => ['a', 'b', 'c'] (iteration order is not guaranteed)
# static last(array) → {*}
Gets the last element of array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to query. |
- Since:
- 0.1.0
Returns the last element of array.
Example
_.last([1, 2, 3]);
// => 3
# static last(array) → {*}
Gets the last element of array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to query. |
- Since:
- 0.1.0
Returns the last element of array.
Example
_.last([1, 2, 3]);
// => 3
# static last(array) → {*}
Gets the last element of array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to query. |
- Since:
- 0.1.0
Returns the last element of array.
Example
_.last([1, 2, 3]);
// => 3
# static lastIndexOf(array, value, fromIndexopt) → {number}
This method is like _.indexOf except that it iterates over elements of
array from right to left.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to inspect. |
||
value |
* | The value to search for. |
||
fromIndex |
number |
<optional> |
array.length-1 | The index to search from. |
- Since:
- 0.1.0
Returns the index of the matched value, else -1.
Example
_.lastIndexOf([1, 2, 1, 2], 2);
// => 3
// Search from the `fromIndex`.
_.lastIndexOf([1, 2, 1, 2], 2, 2);
// => 1
# static lastIndexOf(array, value, fromIndexopt) → {number}
This method is like _.indexOf except that it iterates over elements of
array from right to left.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to inspect. |
||
value |
* | The value to search for. |
||
fromIndex |
number |
<optional> |
array.length-1 | The index to search from. |
- Since:
- 0.1.0
Returns the index of the matched value, else -1.
Example
_.lastIndexOf([1, 2, 1, 2], 2);
// => 3
// Search from the `fromIndex`.
_.lastIndexOf([1, 2, 1, 2], 2, 2);
// => 1
# static map(collection, iterateeopt) → {Array}
Creates an array of values by running each element in collection thru
iteratee. The iteratee is invoked with three arguments:
(value, index|key, collection).
Many lodash methods are guarded to work as iteratees for methods like
_.every, _.filter, _.map, _.mapValues, _.reject, and _.some.
The guarded methods are:
ary, chunk, curry, curryRight, drop, dropRight, every,
fill, invert, parseInt, random, range, rangeRight, repeat,
sampleSize, slice, some, sortBy, split, take, takeRight,
template, trim, trimEnd, trimStart, and words
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
Returns the new mapped array.
Example
function square(n) {
return n * n;
}
_.map([4, 8], square);
// => [16, 64]
_.map({ 'a': 4, 'b': 8 }, square);
// => [16, 64] (iteration order is not guaranteed)
var users = [
{ 'user': 'barney' },
{ 'user': 'fred' }
];
// The `_.property` iteratee shorthand.
_.map(users, 'user');
// => ['barney', 'fred']
# static map(collection, iterateeopt) → {Array}
Creates an array of values by running each element in collection thru
iteratee. The iteratee is invoked with three arguments:
(value, index|key, collection).
Many lodash methods are guarded to work as iteratees for methods like
_.every, _.filter, _.map, _.mapValues, _.reject, and _.some.
The guarded methods are:
ary, chunk, curry, curryRight, drop, dropRight, every,
fill, invert, parseInt, random, range, rangeRight, repeat,
sampleSize, slice, some, sortBy, split, take, takeRight,
template, trim, trimEnd, trimStart, and words
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
Returns the new mapped array.
Example
function square(n) {
return n * n;
}
_.map([4, 8], square);
// => [16, 64]
_.map({ 'a': 4, 'b': 8 }, square);
// => [16, 64] (iteration order is not guaranteed)
var users = [
{ 'user': 'barney' },
{ 'user': 'fred' }
];
// The `_.property` iteratee shorthand.
_.map(users, 'user');
// => ['barney', 'fred']
# static map(collection, iterateeopt) → {Array}
Creates an array of values by running each element in collection thru
iteratee. The iteratee is invoked with three arguments:
(value, index|key, collection).
Many lodash methods are guarded to work as iteratees for methods like
_.every, _.filter, _.map, _.mapValues, _.reject, and _.some.
The guarded methods are:
ary, chunk, curry, curryRight, drop, dropRight, every,
fill, invert, parseInt, random, range, rangeRight, repeat,
sampleSize, slice, some, sortBy, split, take, takeRight,
template, trim, trimEnd, trimStart, and words
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
Returns the new mapped array.
Example
function square(n) {
return n * n;
}
_.map([4, 8], square);
// => [16, 64]
_.map({ 'a': 4, 'b': 8 }, square);
// => [16, 64] (iteration order is not guaranteed)
var users = [
{ 'user': 'barney' },
{ 'user': 'fred' }
];
// The `_.property` iteratee shorthand.
_.map(users, 'user');
// => ['barney', 'fred']
# static mapKeys(object, iterateeopt) → {Object}
The opposite of _.mapValues; this method creates an object with the
same values as object and keys generated by running each own enumerable
string keyed property of object thru iteratee. The iteratee is invoked
with three arguments: (value, key, object).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 3.8.0
- See:
Returns the new mapped object.
Example
_.mapKeys({ 'a': 1, 'b': 2 }, function(value, key) {
return key + value;
});
// => { 'a1': 1, 'b2': 2 }
# static mapKeys(object, iterateeopt) → {Object}
The opposite of _.mapValues; this method creates an object with the
same values as object and keys generated by running each own enumerable
string keyed property of object thru iteratee. The iteratee is invoked
with three arguments: (value, key, object).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 3.8.0
- See:
Returns the new mapped object.
Example
_.mapKeys({ 'a': 1, 'b': 2 }, function(value, key) {
return key + value;
});
// => { 'a1': 1, 'b2': 2 }
# static mapValues(object, iterateeopt) → {Object}
Creates an object with the same keys as object and values generated
by running each own enumerable string keyed property of object thru
iteratee. The iteratee is invoked with three arguments:
(value, key, object).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 2.4.0
- See:
Returns the new mapped object.
Example
var users = {
'fred': { 'user': 'fred', 'age': 40 },
'pebbles': { 'user': 'pebbles', 'age': 1 }
};
_.mapValues(users, function(o) { return o.age; });
// => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed)
// The `_.property` iteratee shorthand.
_.mapValues(users, 'age');
// => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed)
# static mapValues(object, iterateeopt) → {Object}
Creates an object with the same keys as object and values generated
by running each own enumerable string keyed property of object thru
iteratee. The iteratee is invoked with three arguments:
(value, key, object).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 2.4.0
- See:
Returns the new mapped object.
Example
var users = {
'fred': { 'user': 'fred', 'age': 40 },
'pebbles': { 'user': 'pebbles', 'age': 1 }
};
_.mapValues(users, function(o) { return o.age; });
// => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed)
// The `_.property` iteratee shorthand.
_.mapValues(users, 'age');
// => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed)
# static matches(source) → {function}
Creates a function that performs a partial deep comparison between a given
object and source, returning true if the given object has equivalent
property values, else false.
Note: The created function is equivalent to _.isMatch with source
partially applied.
Partial comparisons will match empty array and empty object source
values against any array or object value, respectively. See _.isEqual
for a list of supported value comparisons.
Note: Multiple values can be checked by combining several matchers
using _.overSome
Parameters:
| Name | Type | Description |
|---|---|---|
source |
Object | The object of property values to match. |
- Since:
- 3.0.0
Returns the new spec function.
Example
var objects = [
{ 'a': 1, 'b': 2, 'c': 3 },
{ 'a': 4, 'b': 5, 'c': 6 }
];
_.filter(objects, _.matches({ 'a': 4, 'c': 6 }));
// => [{ 'a': 4, 'b': 5, 'c': 6 }]
// Checking for several possible values
_.filter(objects, _.overSome([_.matches({ 'a': 1 }), _.matches({ 'a': 4 })]));
// => [{ 'a': 1, 'b': 2, 'c': 3 }, { 'a': 4, 'b': 5, 'c': 6 }]
# static matches(source) → {function}
Creates a function that performs a partial deep comparison between a given
object and source, returning true if the given object has equivalent
property values, else false.
Note: The created function is equivalent to _.isMatch with source
partially applied.
Partial comparisons will match empty array and empty object source
values against any array or object value, respectively. See _.isEqual
for a list of supported value comparisons.
Note: Multiple values can be checked by combining several matchers
using _.overSome
Parameters:
| Name | Type | Description |
|---|---|---|
source |
Object | The object of property values to match. |
- Since:
- 3.0.0
Returns the new spec function.
Example
var objects = [
{ 'a': 1, 'b': 2, 'c': 3 },
{ 'a': 4, 'b': 5, 'c': 6 }
];
_.filter(objects, _.matches({ 'a': 4, 'c': 6 }));
// => [{ 'a': 4, 'b': 5, 'c': 6 }]
// Checking for several possible values
_.filter(objects, _.overSome([_.matches({ 'a': 1 }), _.matches({ 'a': 4 })]));
// => [{ 'a': 1, 'b': 2, 'c': 3 }, { 'a': 4, 'b': 5, 'c': 6 }]
# static matches(source) → {function}
Creates a function that performs a partial deep comparison between a given
object and source, returning true if the given object has equivalent
property values, else false.
Note: The created function is equivalent to _.isMatch with source
partially applied.
Partial comparisons will match empty array and empty object source
values against any array or object value, respectively. See _.isEqual
for a list of supported value comparisons.
Note: Multiple values can be checked by combining several matchers
using _.overSome
Parameters:
| Name | Type | Description |
|---|---|---|
source |
Object | The object of property values to match. |
- Since:
- 3.0.0
Returns the new spec function.
Example
var objects = [
{ 'a': 1, 'b': 2, 'c': 3 },
{ 'a': 4, 'b': 5, 'c': 6 }
];
_.filter(objects, _.matches({ 'a': 4, 'c': 6 }));
// => [{ 'a': 4, 'b': 5, 'c': 6 }]
// Checking for several possible values
_.filter(objects, _.overSome([_.matches({ 'a': 1 }), _.matches({ 'a': 4 })]));
// => [{ 'a': 1, 'b': 2, 'c': 3 }, { 'a': 4, 'b': 5, 'c': 6 }]
# static matchesProperty(path, srcValue) → {function}
Creates a function that performs a partial deep comparison between the
value at path of a given object to srcValue, returning true if the
object value is equivalent, else false.
Note: Partial comparisons will match empty array and empty object
srcValue values against any array or object value, respectively. See
_.isEqual for a list of supported value comparisons.
Note: Multiple values can be checked by combining several matchers
using _.overSome
Parameters:
| Name | Type | Description |
|---|---|---|
path |
Array | string | The path of the property to get. |
srcValue |
* | The value to match. |
- Since:
- 3.2.0
Returns the new spec function.
Example
var objects = [
{ 'a': 1, 'b': 2, 'c': 3 },
{ 'a': 4, 'b': 5, 'c': 6 }
];
_.find(objects, _.matchesProperty('a', 4));
// => { 'a': 4, 'b': 5, 'c': 6 }
// Checking for several possible values
_.filter(objects, _.overSome([_.matchesProperty('a', 1), _.matchesProperty('a', 4)]));
// => [{ 'a': 1, 'b': 2, 'c': 3 }, { 'a': 4, 'b': 5, 'c': 6 }]
# static matchesProperty(path, srcValue) → {function}
Creates a function that performs a partial deep comparison between the
value at path of a given object to srcValue, returning true if the
object value is equivalent, else false.
Note: Partial comparisons will match empty array and empty object
srcValue values against any array or object value, respectively. See
_.isEqual for a list of supported value comparisons.
Note: Multiple values can be checked by combining several matchers
using _.overSome
Parameters:
| Name | Type | Description |
|---|---|---|
path |
Array | string | The path of the property to get. |
srcValue |
* | The value to match. |
- Since:
- 3.2.0
Returns the new spec function.
Example
var objects = [
{ 'a': 1, 'b': 2, 'c': 3 },
{ 'a': 4, 'b': 5, 'c': 6 }
];
_.find(objects, _.matchesProperty('a', 4));
// => { 'a': 4, 'b': 5, 'c': 6 }
// Checking for several possible values
_.filter(objects, _.overSome([_.matchesProperty('a', 1), _.matchesProperty('a', 4)]));
// => [{ 'a': 1, 'b': 2, 'c': 3 }, { 'a': 4, 'b': 5, 'c': 6 }]
# static max(array) → {*}
Computes the maximum value of array. If array is empty or falsey,
undefined is returned.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to iterate over. |
- Since:
- 0.1.0
Returns the maximum value.
Example
_.max([4, 2, 8, 6]);
// => 8
_.max([]);
// => undefined
# static max(array) → {*}
Computes the maximum value of array. If array is empty or falsey,
undefined is returned.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to iterate over. |
- Since:
- 0.1.0
Returns the maximum value.
Example
_.max([4, 2, 8, 6]);
// => 8
_.max([]);
// => undefined
# static max(array) → {*}
Computes the maximum value of array. If array is empty or falsey,
undefined is returned.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to iterate over. |
- Since:
- 0.1.0
Returns the maximum value.
Example
_.max([4, 2, 8, 6]);
// => 8
_.max([]);
// => undefined
# static maxBy(array, iterateeopt) → {*}
This method is like _.max except that it accepts iteratee which is
invoked for each element in array to generate the criterion by which
the value is ranked. The iteratee is invoked with one argument: (value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.0.0
Returns the maximum value.
Example
var objects = [{ 'n': 1 }, { 'n': 2 }];
_.maxBy(objects, function(o) { return o.n; });
// => { 'n': 2 }
// The `_.property` iteratee shorthand.
_.maxBy(objects, 'n');
// => { 'n': 2 }
# static maxBy(array, iterateeopt) → {*}
This method is like _.max except that it accepts iteratee which is
invoked for each element in array to generate the criterion by which
the value is ranked. The iteratee is invoked with one argument: (value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.0.0
Returns the maximum value.
Example
var objects = [{ 'n': 1 }, { 'n': 2 }];
_.maxBy(objects, function(o) { return o.n; });
// => { 'n': 2 }
// The `_.property` iteratee shorthand.
_.maxBy(objects, 'n');
// => { 'n': 2 }
# static mean(array) → {number}
Computes the mean of the values in array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to iterate over. |
- Since:
- 4.0.0
Returns the mean.
Example
_.mean([4, 2, 8, 6]);
// => 5
# static mean(array) → {number}
Computes the mean of the values in array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to iterate over. |
- Since:
- 4.0.0
Returns the mean.
Example
_.mean([4, 2, 8, 6]);
// => 5
# static meanBy(array, iterateeopt) → {number}
This method is like _.mean except that it accepts iteratee which is
invoked for each element in array to generate the value to be averaged.
The iteratee is invoked with one argument: (value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.7.0
Returns the mean.
Example
var objects = [{ 'n': 4 }, { 'n': 2 }, { 'n': 8 }, { 'n': 6 }];
_.meanBy(objects, function(o) { return o.n; });
// => 5
// The `_.property` iteratee shorthand.
_.meanBy(objects, 'n');
// => 5
# static meanBy(array, iterateeopt) → {number}
This method is like _.mean except that it accepts iteratee which is
invoked for each element in array to generate the value to be averaged.
The iteratee is invoked with one argument: (value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.7.0
Returns the mean.
Example
var objects = [{ 'n': 4 }, { 'n': 2 }, { 'n': 8 }, { 'n': 6 }];
_.meanBy(objects, function(o) { return o.n; });
// => 5
// The `_.property` iteratee shorthand.
_.meanBy(objects, 'n');
// => 5
# static memoize(func, resolveropt) → {function}
Creates a function that memoizes the result of func. If resolver is
provided, it determines the cache key for storing the result based on the
arguments provided to the memoized function. By default, the first argument
provided to the memoized function is used as the map cache key. The func
is invoked with the this binding of the memoized function.
Note: The cache is exposed as the cache property on the memoized
function. Its creation may be customized by replacing the _.memoize.Cache
constructor with one whose instances implement the
Map
method interface of clear, delete, get, has, and set.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
func |
function | The function to have its output memoized. |
|
resolver |
function |
<optional> |
The function to resolve the cache key. |
- Since:
- 0.1.0
Returns the new memoized function.
Example
var object = { 'a': 1, 'b': 2 };
var other = { 'c': 3, 'd': 4 };
var values = _.memoize(_.values);
values(object);
// => [1, 2]
values(other);
// => [3, 4]
object.a = 2;
values(object);
// => [1, 2]
// Modify the result cache.
values.cache.set(object, ['a', 'b']);
values(object);
// => ['a', 'b']
// Replace `_.memoize.Cache`.
_.memoize.Cache = WeakMap;
# static memoize(func, resolveropt) → {function}
Creates a function that memoizes the result of func. If resolver is
provided, it determines the cache key for storing the result based on the
arguments provided to the memoized function. By default, the first argument
provided to the memoized function is used as the map cache key. The func
is invoked with the this binding of the memoized function.
Note: The cache is exposed as the cache property on the memoized
function. Its creation may be customized by replacing the _.memoize.Cache
constructor with one whose instances implement the
Map
method interface of clear, delete, get, has, and set.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
func |
function | The function to have its output memoized. |
|
resolver |
function |
<optional> |
The function to resolve the cache key. |
- Since:
- 0.1.0
Returns the new memoized function.
Example
var object = { 'a': 1, 'b': 2 };
var other = { 'c': 3, 'd': 4 };
var values = _.memoize(_.values);
values(object);
// => [1, 2]
values(other);
// => [3, 4]
object.a = 2;
values(object);
// => [1, 2]
// Modify the result cache.
values.cache.set(object, ['a', 'b']);
values(object);
// => ['a', 'b']
// Replace `_.memoize.Cache`.
_.memoize.Cache = WeakMap;
# static min(array) → {*}
Computes the minimum value of array. If array is empty or falsey,
undefined is returned.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to iterate over. |
- Since:
- 0.1.0
Returns the minimum value.
Example
_.min([4, 2, 8, 6]);
// => 2
_.min([]);
// => undefined
# static min(array) → {*}
Computes the minimum value of array. If array is empty or falsey,
undefined is returned.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to iterate over. |
- Since:
- 0.1.0
Returns the minimum value.
Example
_.min([4, 2, 8, 6]);
// => 2
_.min([]);
// => undefined
# static min(array) → {*}
Computes the minimum value of array. If array is empty or falsey,
undefined is returned.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to iterate over. |
- Since:
- 0.1.0
Returns the minimum value.
Example
_.min([4, 2, 8, 6]);
// => 2
_.min([]);
// => undefined
# static minBy(array, iterateeopt) → {*}
This method is like _.min except that it accepts iteratee which is
invoked for each element in array to generate the criterion by which
the value is ranked. The iteratee is invoked with one argument: (value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.0.0
Returns the minimum value.
Example
var objects = [{ 'n': 1 }, { 'n': 2 }];
_.minBy(objects, function(o) { return o.n; });
// => { 'n': 1 }
// The `_.property` iteratee shorthand.
_.minBy(objects, 'n');
// => { 'n': 1 }
# static minBy(array, iterateeopt) → {*}
This method is like _.min except that it accepts iteratee which is
invoked for each element in array to generate the criterion by which
the value is ranked. The iteratee is invoked with one argument: (value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.0.0
Returns the minimum value.
Example
var objects = [{ 'n': 1 }, { 'n': 2 }];
_.minBy(objects, function(o) { return o.n; });
// => { 'n': 1 }
// The `_.property` iteratee shorthand.
_.minBy(objects, 'n');
// => { 'n': 1 }
# static mixin(objectopt, source, optionsopt) → {function|Object}
Adds all own enumerable string keyed function properties of a source
object to the destination object. If object is a function, then methods
are added to its prototype as well.
Note: Use _.runInContext to create a pristine lodash function to
avoid conflicts caused by modifying the original.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
function | Object |
<optional> |
lodash | The destination object. |
source |
Object | The object of functions to add. |
||
options |
Object |
<optional> |
{} | The options object. |
chain |
boolean |
<optional> |
true | Specify whether mixins are chainable. |
- Since:
- 0.1.0
Returns object.
Example
function vowels(string) {
return _.filter(string, function(v) {
return /[aeiou]/i.test(v);
});
}
_.mixin({ 'vowels': vowels });
_.vowels('fred');
// => ['e']
_('fred').vowels().value();
// => ['e']
_.mixin({ 'vowels': vowels }, { 'chain': false });
_('fred').vowels();
// => ['e']
# static mixin(objectopt, source, optionsopt) → {function|Object}
Adds all own enumerable string keyed function properties of a source
object to the destination object. If object is a function, then methods
are added to its prototype as well.
Note: Use _.runInContext to create a pristine lodash function to
avoid conflicts caused by modifying the original.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
function | Object |
<optional> |
lodash | The destination object. |
source |
Object | The object of functions to add. |
||
options |
Object |
<optional> |
{} | The options object. |
chain |
boolean |
<optional> |
true | Specify whether mixins are chainable. |
- Since:
- 0.1.0
Returns object.
Example
function vowels(string) {
return _.filter(string, function(v) {
return /[aeiou]/i.test(v);
});
}
_.mixin({ 'vowels': vowels });
_.vowels('fred');
// => ['e']
_('fred').vowels().value();
// => ['e']
_.mixin({ 'vowels': vowels }, { 'chain': false });
_('fred').vowels();
// => ['e']
# static mixin(objectopt, source, optionsopt) → {function|Object}
Adds all own enumerable string keyed function properties of a source
object to the destination object. If object is a function, then methods
are added to its prototype as well.
Note: Use _.runInContext to create a pristine lodash function to
avoid conflicts caused by modifying the original.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
function | Object |
<optional> |
lodash | The destination object. |
source |
Object | The object of functions to add. |
||
options |
Object |
<optional> |
{} | The options object. |
chain |
boolean |
<optional> |
true | Specify whether mixins are chainable. |
- Since:
- 0.1.0
Returns object.
Example
function vowels(string) {
return _.filter(string, function(v) {
return /[aeiou]/i.test(v);
});
}
_.mixin({ 'vowels': vowels });
_.vowels('fred');
// => ['e']
_('fred').vowels().value();
// => ['e']
_.mixin({ 'vowels': vowels }, { 'chain': false });
_('fred').vowels();
// => ['e']
# static negate(predicate) → {function}
Creates a function that negates the result of the predicate func. The
func predicate is invoked with the this binding and arguments of the
created function.
Parameters:
| Name | Type | Description |
|---|---|---|
predicate |
function | The predicate to negate. |
- Since:
- 3.0.0
Returns the new negated function.
Example
function isEven(n) {
return n % 2 == 0;
}
_.filter([1, 2, 3, 4, 5, 6], _.negate(isEven));
// => [1, 3, 5]
# static negate(predicate) → {function}
Creates a function that negates the result of the predicate func. The
func predicate is invoked with the this binding and arguments of the
created function.
Parameters:
| Name | Type | Description |
|---|---|---|
predicate |
function | The predicate to negate. |
- Since:
- 3.0.0
Returns the new negated function.
Example
function isEven(n) {
return n % 2 == 0;
}
_.filter([1, 2, 3, 4, 5, 6], _.negate(isEven));
// => [1, 3, 5]
# static negate(predicate) → {function}
Creates a function that negates the result of the predicate func. The
func predicate is invoked with the this binding and arguments of the
created function.
Parameters:
| Name | Type | Description |
|---|---|---|
predicate |
function | The predicate to negate. |
- Since:
- 3.0.0
Returns the new negated function.
Example
function isEven(n) {
return n % 2 == 0;
}
_.filter([1, 2, 3, 4, 5, 6], _.negate(isEven));
// => [1, 3, 5]
# static noConflict() → {function}
Reverts the _ variable to its previous value and returns a reference to
the lodash function.
- Since:
- 0.1.0
Returns the lodash function.
Example
var lodash = _.noConflict();
# static noConflict() → {function}
Reverts the _ variable to its previous value and returns a reference to
the lodash function.
- Since:
- 0.1.0
Returns the lodash function.
Example
var lodash = _.noConflict();
# static noop()
This method returns undefined.
- Since:
- 2.3.0
Example
_.times(2, _.noop);
// => [undefined, undefined]
# static noop()
This method returns undefined.
- Since:
- 2.3.0
Example
_.times(2, _.noop);
// => [undefined, undefined]
# static noop()
This method returns undefined.
- Since:
- 2.3.0
Example
_.times(2, _.noop);
// => [undefined, undefined]
# static now() → {number}
Gets the timestamp of the number of milliseconds that have elapsed since the Unix epoch (1 January 1970 00:00:00 UTC).
- Since:
- 2.4.0
Returns the timestamp.
Example
_.defer(function(stamp) {
console.log(_.now() - stamp);
}, _.now());
// => Logs the number of milliseconds it took for the deferred invocation.
# static nth(array, nopt) → {*}
Gets the element at index n of array. If n is negative, the nth
element from the end is returned.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
n |
number |
<optional> |
0 | The index of the element to return. |
- Since:
- 4.11.0
Returns the nth element of array.
Example
var array = ['a', 'b', 'c', 'd'];
_.nth(array, 1);
// => 'b'
_.nth(array, -2);
// => 'c';
# static nth(array, nopt) → {*}
Gets the element at index n of array. If n is negative, the nth
element from the end is returned.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
n |
number |
<optional> |
0 | The index of the element to return. |
- Since:
- 4.11.0
Returns the nth element of array.
Example
var array = ['a', 'b', 'c', 'd'];
_.nth(array, 1);
// => 'b'
_.nth(array, -2);
// => 'c';
# static nthArg(nopt) → {function}
Creates a function that gets the argument at index n. If n is negative,
the nth argument from the end is returned.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
n |
number |
<optional> |
0 | The index of the argument to return. |
- Since:
- 4.0.0
Returns the new pass-thru function.
Example
var func = _.nthArg(1);
func('a', 'b', 'c', 'd');
// => 'b'
var func = _.nthArg(-2);
func('a', 'b', 'c', 'd');
// => 'c'
# static nthArg(nopt) → {function}
Creates a function that gets the argument at index n. If n is negative,
the nth argument from the end is returned.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
n |
number |
<optional> |
0 | The index of the argument to return. |
- Since:
- 4.0.0
Returns the new pass-thru function.
Example
var func = _.nthArg(1);
func('a', 'b', 'c', 'd');
// => 'b'
var func = _.nthArg(-2);
func('a', 'b', 'c', 'd');
// => 'c'
# static omitBy(object, predicateopt) → {Object}
The opposite of _.pickBy; this method creates an object composed of
the own and inherited enumerable string keyed properties of object that
predicate doesn't return truthy for. The predicate is invoked with two
arguments: (value, key).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The source object. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per property. |
- Since:
- 4.0.0
Returns the new object.
Example
var object = { 'a': 1, 'b': '2', 'c': 3 };
_.omitBy(object, _.isNumber);
// => { 'b': '2' }
# static omitBy(object, predicateopt) → {Object}
The opposite of _.pickBy; this method creates an object composed of
the own and inherited enumerable string keyed properties of object that
predicate doesn't return truthy for. The predicate is invoked with two
arguments: (value, key).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The source object. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per property. |
- Since:
- 4.0.0
Returns the new object.
Example
var object = { 'a': 1, 'b': '2', 'c': 3 };
_.omitBy(object, _.isNumber);
// => { 'b': '2' }
# static once(func) → {function}
Creates a function that is restricted to invoking func once. Repeat calls
to the function return the value of the first invocation. The func is
invoked with the this binding and arguments of the created function.
Parameters:
| Name | Type | Description |
|---|---|---|
func |
function | The function to restrict. |
- Since:
- 0.1.0
Returns the new restricted function.
Example
var initialize = _.once(createApplication);
initialize();
initialize();
// => `createApplication` is invoked once
# static once(func) → {function}
Creates a function that is restricted to invoking func once. Repeat calls
to the function return the value of the first invocation. The func is
invoked with the this binding and arguments of the created function.
Parameters:
| Name | Type | Description |
|---|---|---|
func |
function | The function to restrict. |
- Since:
- 0.1.0
Returns the new restricted function.
Example
var initialize = _.once(createApplication);
initialize();
initialize();
// => `createApplication` is invoked once
# static once(func) → {function}
Creates a function that is restricted to invoking func once. Repeat calls
to the function return the value of the first invocation. The func is
invoked with the this binding and arguments of the created function.
Parameters:
| Name | Type | Description |
|---|---|---|
func |
function | The function to restrict. |
- Since:
- 0.1.0
Returns the new restricted function.
Example
var initialize = _.once(createApplication);
initialize();
initialize();
// => `createApplication` is invoked once
# static orderBy(collection, iterateesopt, ordersopt) → {Array}
This method is like _.sortBy except that it allows specifying the sort
orders of the iteratees to sort by. If orders is unspecified, all values
are sorted in ascending order. Otherwise, specify an order of "desc" for
descending or "asc" for ascending sort order of corresponding values.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratees |
Array.<Array> | Array.<function()> | Array.<Object> | Array.<string> |
<optional> |
[_.identity] | The iteratees to sort by. |
orders |
Array.<string> |
<optional> |
The sort orders of |
- Since:
- 4.0.0
Returns the new sorted array.
Example
var users = [
{ 'user': 'fred', 'age': 48 },
{ 'user': 'barney', 'age': 34 },
{ 'user': 'fred', 'age': 40 },
{ 'user': 'barney', 'age': 36 }
];
// Sort by `user` in ascending order and by `age` in descending order.
_.orderBy(users, ['user', 'age'], ['asc', 'desc']);
// => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 40]]
# static orderBy(collection, iterateesopt, ordersopt) → {Array}
This method is like _.sortBy except that it allows specifying the sort
orders of the iteratees to sort by. If orders is unspecified, all values
are sorted in ascending order. Otherwise, specify an order of "desc" for
descending or "asc" for ascending sort order of corresponding values.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratees |
Array.<Array> | Array.<function()> | Array.<Object> | Array.<string> |
<optional> |
[_.identity] | The iteratees to sort by. |
orders |
Array.<string> |
<optional> |
The sort orders of |
- Since:
- 4.0.0
Returns the new sorted array.
Example
var users = [
{ 'user': 'fred', 'age': 48 },
{ 'user': 'barney', 'age': 34 },
{ 'user': 'fred', 'age': 40 },
{ 'user': 'barney', 'age': 36 }
];
// Sort by `user` in ascending order and by `age` in descending order.
_.orderBy(users, ['user', 'age'], ['asc', 'desc']);
// => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 40]]
# static pad(stringopt, lengthopt, charsopt) → {string}
Pads string on the left and right sides if it's shorter than length.
Padding characters are truncated if they can't be evenly divided by length.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to pad. |
length |
number |
<optional> |
0 | The padding length. |
chars |
string |
<optional> |
' ' | The string used as padding. |
- Since:
- 3.0.0
Returns the padded string.
Example
_.pad('abc', 8);
// => ' abc '
_.pad('abc', 8, '_-');
// => '_-abc_-_'
_.pad('abc', 3);
// => 'abc'
# static pad(stringopt, lengthopt, charsopt) → {string}
Pads string on the left and right sides if it's shorter than length.
Padding characters are truncated if they can't be evenly divided by length.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to pad. |
length |
number |
<optional> |
0 | The padding length. |
chars |
string |
<optional> |
' ' | The string used as padding. |
- Since:
- 3.0.0
Returns the padded string.
Example
_.pad('abc', 8);
// => ' abc '
_.pad('abc', 8, '_-');
// => '_-abc_-_'
_.pad('abc', 3);
// => 'abc'
# static padEnd(stringopt, lengthopt, charsopt) → {string}
Pads string on the right side if it's shorter than length. Padding
characters are truncated if they exceed length.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to pad. |
length |
number |
<optional> |
0 | The padding length. |
chars |
string |
<optional> |
' ' | The string used as padding. |
- Since:
- 4.0.0
Returns the padded string.
Example
_.padEnd('abc', 6);
// => 'abc '
_.padEnd('abc', 6, '_-');
// => 'abc_-_'
_.padEnd('abc', 3);
// => 'abc'
# static padEnd(stringopt, lengthopt, charsopt) → {string}
Pads string on the right side if it's shorter than length. Padding
characters are truncated if they exceed length.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to pad. |
length |
number |
<optional> |
0 | The padding length. |
chars |
string |
<optional> |
' ' | The string used as padding. |
- Since:
- 4.0.0
Returns the padded string.
Example
_.padEnd('abc', 6);
// => 'abc '
_.padEnd('abc', 6, '_-');
// => 'abc_-_'
_.padEnd('abc', 3);
// => 'abc'
# static padStart(stringopt, lengthopt, charsopt) → {string}
Pads string on the left side if it's shorter than length. Padding
characters are truncated if they exceed length.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to pad. |
length |
number |
<optional> |
0 | The padding length. |
chars |
string |
<optional> |
' ' | The string used as padding. |
- Since:
- 4.0.0
Returns the padded string.
Example
_.padStart('abc', 6);
// => ' abc'
_.padStart('abc', 6, '_-');
// => '_-_abc'
_.padStart('abc', 3);
// => 'abc'
# static padStart(stringopt, lengthopt, charsopt) → {string}
Pads string on the left side if it's shorter than length. Padding
characters are truncated if they exceed length.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to pad. |
length |
number |
<optional> |
0 | The padding length. |
chars |
string |
<optional> |
' ' | The string used as padding. |
- Since:
- 4.0.0
Returns the padded string.
Example
_.padStart('abc', 6);
// => ' abc'
_.padStart('abc', 6, '_-');
// => '_-_abc'
_.padStart('abc', 3);
// => 'abc'
# static parseInt(string, radixopt) → {number}
Converts string to an integer of the specified radix. If radix is
undefined or 0, a radix of 10 is used unless value is a
hexadecimal, in which case a radix of 16 is used.
Note: This method aligns with the
ES5 implementation of parseInt.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string | The string to convert. |
||
radix |
number |
<optional> |
10 | The radix to interpret |
- Since:
- 1.1.0
Returns the converted integer.
Example
_.parseInt('08');
// => 8
_.map(['6', '08', '10'], _.parseInt);
// => [6, 8, 10]
# static parseInt(string, radixopt) → {number}
Converts string to an integer of the specified radix. If radix is
undefined or 0, a radix of 10 is used unless value is a
hexadecimal, in which case a radix of 16 is used.
Note: This method aligns with the
ES5 implementation of parseInt.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string | The string to convert. |
||
radix |
number |
<optional> |
10 | The radix to interpret |
- Since:
- 1.1.0
Returns the converted integer.
Example
_.parseInt('08');
// => 8
_.map(['6', '08', '10'], _.parseInt);
// => [6, 8, 10]
# static pickBy(object, predicateopt) → {Object}
Creates an object composed of the object properties predicate returns
truthy for. The predicate is invoked with two arguments: (value, key).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The source object. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per property. |
- Since:
- 4.0.0
Returns the new object.
Example
var object = { 'a': 1, 'b': '2', 'c': 3 };
_.pickBy(object, _.isNumber);
// => { 'a': 1, 'c': 3 }
# static pickBy(object, predicateopt) → {Object}
Creates an object composed of the object properties predicate returns
truthy for. The predicate is invoked with two arguments: (value, key).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The source object. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per property. |
- Since:
- 4.0.0
Returns the new object.
Example
var object = { 'a': 1, 'b': '2', 'c': 3 };
_.pickBy(object, _.isNumber);
// => { 'a': 1, 'c': 3 }
# static property(path) → {function}
Creates a function that returns the value at path of a given object.
Parameters:
| Name | Type | Description |
|---|---|---|
path |
Array | string | The path of the property to get. |
- Since:
- 2.4.0
Returns the new accessor function.
Example
var objects = [
{ 'a': { 'b': 2 } },
{ 'a': { 'b': 1 } }
];
_.map(objects, _.property('a.b'));
// => [2, 1]
_.map(_.sortBy(objects, _.property(['a', 'b'])), 'a.b');
// => [1, 2]
# static property(path) → {function}
Creates a function that returns the value at path of a given object.
Parameters:
| Name | Type | Description |
|---|---|---|
path |
Array | string | The path of the property to get. |
- Since:
- 2.4.0
Returns the new accessor function.
Example
var objects = [
{ 'a': { 'b': 2 } },
{ 'a': { 'b': 1 } }
];
_.map(objects, _.property('a.b'));
// => [2, 1]
_.map(_.sortBy(objects, _.property(['a', 'b'])), 'a.b');
// => [1, 2]
# static propertyOf(object) → {function}
The opposite of _.property; this method creates a function that returns
the value at a given path of object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
- Since:
- 3.0.0
Returns the new accessor function.
Example
var array = [0, 1, 2],
object = { 'a': array, 'b': array, 'c': array };
_.map(['a[2]', 'c[0]'], _.propertyOf(object));
// => [2, 0]
_.map([['a', '2'], ['c', '0']], _.propertyOf(object));
// => [2, 0]
# static propertyOf(object) → {function}
The opposite of _.property; this method creates a function that returns
the value at a given path of object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
- Since:
- 3.0.0
Returns the new accessor function.
Example
var array = [0, 1, 2],
object = { 'a': array, 'b': array, 'c': array };
_.map(['a[2]', 'c[0]'], _.propertyOf(object));
// => [2, 0]
_.map([['a', '2'], ['c', '0']], _.propertyOf(object));
// => [2, 0]
# static pullAll(array, values) → {Array}
This method is like _.pull except that it accepts an array of values to remove.
Note: Unlike _.difference, this method mutates array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to modify. |
values |
Array | The values to remove. |
- Since:
- 4.0.0
Returns array.
Example
var array = ['a', 'b', 'c', 'a', 'b', 'c'];
_.pullAll(array, ['a', 'c']);
console.log(array);
// => ['b', 'b']
# static pullAll(array, values) → {Array}
This method is like _.pull except that it accepts an array of values to remove.
Note: Unlike _.difference, this method mutates array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to modify. |
values |
Array | The values to remove. |
- Since:
- 4.0.0
Returns array.
Example
var array = ['a', 'b', 'c', 'a', 'b', 'c'];
_.pullAll(array, ['a', 'c']);
console.log(array);
// => ['b', 'b']
# static pullAllBy(array, values, iterateeopt) → {Array}
This method is like _.pullAll except that it accepts iteratee which is
invoked for each element of array and values to generate the criterion
by which they're compared. The iteratee is invoked with one argument: (value).
Note: Unlike _.differenceBy, this method mutates array.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to modify. |
||
values |
Array | The values to remove. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.0.0
Returns array.
Example
var array = [{ 'x': 1 }, { 'x': 2 }, { 'x': 3 }, { 'x': 1 }];
_.pullAllBy(array, [{ 'x': 1 }, { 'x': 3 }], 'x');
console.log(array);
// => [{ 'x': 2 }]
# static pullAllBy(array, values, iterateeopt) → {Array}
This method is like _.pullAll except that it accepts iteratee which is
invoked for each element of array and values to generate the criterion
by which they're compared. The iteratee is invoked with one argument: (value).
Note: Unlike _.differenceBy, this method mutates array.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to modify. |
||
values |
Array | The values to remove. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.0.0
Returns array.
Example
var array = [{ 'x': 1 }, { 'x': 2 }, { 'x': 3 }, { 'x': 1 }];
_.pullAllBy(array, [{ 'x': 1 }, { 'x': 3 }], 'x');
console.log(array);
// => [{ 'x': 2 }]
# static pullAllWith(array, values, comparatoropt) → {Array}
This method is like _.pullAll except that it accepts comparator which
is invoked to compare elements of array to values. The comparator is
invoked with two arguments: (arrVal, othVal).
Note: Unlike _.differenceWith, this method mutates array.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
array |
Array | The array to modify. |
|
values |
Array | The values to remove. |
|
comparator |
function |
<optional> |
The comparator invoked per element. |
- Since:
- 4.6.0
Returns array.
Example
var array = [{ 'x': 1, 'y': 2 }, { 'x': 3, 'y': 4 }, { 'x': 5, 'y': 6 }];
_.pullAllWith(array, [{ 'x': 3, 'y': 4 }], _.isEqual);
console.log(array);
// => [{ 'x': 1, 'y': 2 }, { 'x': 5, 'y': 6 }]
# static pullAllWith(array, values, comparatoropt) → {Array}
This method is like _.pullAll except that it accepts comparator which
is invoked to compare elements of array to values. The comparator is
invoked with two arguments: (arrVal, othVal).
Note: Unlike _.differenceWith, this method mutates array.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
array |
Array | The array to modify. |
|
values |
Array | The values to remove. |
|
comparator |
function |
<optional> |
The comparator invoked per element. |
- Since:
- 4.6.0
Returns array.
Example
var array = [{ 'x': 1, 'y': 2 }, { 'x': 3, 'y': 4 }, { 'x': 5, 'y': 6 }];
_.pullAllWith(array, [{ 'x': 3, 'y': 4 }], _.isEqual);
console.log(array);
// => [{ 'x': 1, 'y': 2 }, { 'x': 5, 'y': 6 }]
# static random(loweropt, upperopt, floatingopt) → {number}
Produces a random number between the inclusive lower and upper bounds.
If only one argument is provided a number between 0 and the given number
is returned. If floating is true, or either lower or upper are
floats, a floating-point number is returned instead of an integer.
Note: JavaScript follows the IEEE-754 standard for resolving floating-point values which can produce unexpected results.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
lower |
number |
<optional> |
0 | The lower bound. |
upper |
number |
<optional> |
1 | The upper bound. |
floating |
boolean |
<optional> |
Specify returning a floating-point number. |
- Since:
- 0.7.0
Returns the random number.
Example
_.random(0, 5);
// => an integer between 0 and 5
_.random(5);
// => also an integer between 0 and 5
_.random(5, true);
// => a floating-point number between 0 and 5
_.random(1.2, 5.2);
// => a floating-point number between 1.2 and 5.2
# static random(loweropt, upperopt, floatingopt) → {number}
Produces a random number between the inclusive lower and upper bounds.
If only one argument is provided a number between 0 and the given number
is returned. If floating is true, or either lower or upper are
floats, a floating-point number is returned instead of an integer.
Note: JavaScript follows the IEEE-754 standard for resolving floating-point values which can produce unexpected results.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
lower |
number |
<optional> |
0 | The lower bound. |
upper |
number |
<optional> |
1 | The upper bound. |
floating |
boolean |
<optional> |
Specify returning a floating-point number. |
- Since:
- 0.7.0
Returns the random number.
Example
_.random(0, 5);
// => an integer between 0 and 5
_.random(5);
// => also an integer between 0 and 5
_.random(5, true);
// => a floating-point number between 0 and 5
_.random(1.2, 5.2);
// => a floating-point number between 1.2 and 5.2
# static reduce(collection, iterateeopt, accumulatoropt) → {*}
Reduces collection to a value which is the accumulated result of running
each element in collection thru iteratee, where each successive
invocation is supplied the return value of the previous. If accumulator
is not given, the first element of collection is used as the initial
value. The iteratee is invoked with four arguments:
(accumulator, value, index|key, collection).
Many lodash methods are guarded to work as iteratees for methods like
_.reduce, _.reduceRight, and _.transform.
The guarded methods are:
assign, defaults, defaultsDeep, includes, merge, orderBy,
and sortBy
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
accumulator |
* |
<optional> |
The initial value. |
- Since:
- 0.1.0
- See:
Returns the accumulated value.
Example
_.reduce([1, 2], function(sum, n) {
return sum + n;
}, 0);
// => 3
_.reduce({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) {
(result[value] || (result[value] = [])).push(key);
return result;
}, {});
// => { '1': ['a', 'c'], '2': ['b'] } (iteration order is not guaranteed)
# static reduce(collection, iterateeopt, accumulatoropt) → {*}
Reduces collection to a value which is the accumulated result of running
each element in collection thru iteratee, where each successive
invocation is supplied the return value of the previous. If accumulator
is not given, the first element of collection is used as the initial
value. The iteratee is invoked with four arguments:
(accumulator, value, index|key, collection).
Many lodash methods are guarded to work as iteratees for methods like
_.reduce, _.reduceRight, and _.transform.
The guarded methods are:
assign, defaults, defaultsDeep, includes, merge, orderBy,
and sortBy
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
accumulator |
* |
<optional> |
The initial value. |
- Since:
- 0.1.0
- See:
Returns the accumulated value.
Example
_.reduce([1, 2], function(sum, n) {
return sum + n;
}, 0);
// => 3
_.reduce({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) {
(result[value] || (result[value] = [])).push(key);
return result;
}, {});
// => { '1': ['a', 'c'], '2': ['b'] } (iteration order is not guaranteed)
# static reduce(collection, iterateeopt, accumulatoropt) → {*}
Reduces collection to a value which is the accumulated result of running
each element in collection thru iteratee, where each successive
invocation is supplied the return value of the previous. If accumulator
is not given, the first element of collection is used as the initial
value. The iteratee is invoked with four arguments:
(accumulator, value, index|key, collection).
Many lodash methods are guarded to work as iteratees for methods like
_.reduce, _.reduceRight, and _.transform.
The guarded methods are:
assign, defaults, defaultsDeep, includes, merge, orderBy,
and sortBy
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
accumulator |
* |
<optional> |
The initial value. |
- Since:
- 0.1.0
- See:
Returns the accumulated value.
Example
_.reduce([1, 2], function(sum, n) {
return sum + n;
}, 0);
// => 3
_.reduce({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) {
(result[value] || (result[value] = [])).push(key);
return result;
}, {});
// => { '1': ['a', 'c'], '2': ['b'] } (iteration order is not guaranteed)
# static reduceRight(collection, iterateeopt, accumulatoropt) → {*}
This method is like _.reduce except that it iterates over elements of
collection from right to left.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
accumulator |
* |
<optional> |
The initial value. |
- Since:
- 0.1.0
- See:
Returns the accumulated value.
Example
var array = [[0, 1], [2, 3], [4, 5]];
_.reduceRight(array, function(flattened, other) {
return flattened.concat(other);
}, []);
// => [4, 5, 2, 3, 0, 1]
# static reduceRight(collection, iterateeopt, accumulatoropt) → {*}
This method is like _.reduce except that it iterates over elements of
collection from right to left.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
accumulator |
* |
<optional> |
The initial value. |
- Since:
- 0.1.0
- See:
Returns the accumulated value.
Example
var array = [[0, 1], [2, 3], [4, 5]];
_.reduceRight(array, function(flattened, other) {
return flattened.concat(other);
}, []);
// => [4, 5, 2, 3, 0, 1]
# static reject(collection, predicateopt) → {Array}
The opposite of _.filter; this method returns the elements of collection
that predicate does not return truthy for.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
- See:
Returns the new filtered array.
Example
var users = [
{ 'user': 'barney', 'age': 36, 'active': false },
{ 'user': 'fred', 'age': 40, 'active': true }
];
_.reject(users, function(o) { return !o.active; });
// => objects for ['fred']
// The `_.matches` iteratee shorthand.
_.reject(users, { 'age': 40, 'active': true });
// => objects for ['barney']
// The `_.matchesProperty` iteratee shorthand.
_.reject(users, ['active', false]);
// => objects for ['fred']
// The `_.property` iteratee shorthand.
_.reject(users, 'active');
// => objects for ['barney']
# static reject(collection, predicateopt) → {Array}
The opposite of _.filter; this method returns the elements of collection
that predicate does not return truthy for.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
- See:
Returns the new filtered array.
Example
var users = [
{ 'user': 'barney', 'age': 36, 'active': false },
{ 'user': 'fred', 'age': 40, 'active': true }
];
_.reject(users, function(o) { return !o.active; });
// => objects for ['fred']
// The `_.matches` iteratee shorthand.
_.reject(users, { 'age': 40, 'active': true });
// => objects for ['barney']
// The `_.matchesProperty` iteratee shorthand.
_.reject(users, ['active', false]);
// => objects for ['fred']
// The `_.property` iteratee shorthand.
_.reject(users, 'active');
// => objects for ['barney']
# static remove(array, predicateopt) → {Array}
Removes all elements from array that predicate returns truthy for
and returns an array of the removed elements. The predicate is invoked
with three arguments: (value, index, array).
Note: Unlike _.filter, this method mutates array. Use _.pull
to pull elements from an array by value.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to modify. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 2.0.0
Returns the new array of removed elements.
Example
var array = [1, 2, 3, 4];
var evens = _.remove(array, function(n) {
return n % 2 == 0;
});
console.log(array);
// => [1, 3]
console.log(evens);
// => [2, 4]
# static remove(array, predicateopt) → {Array}
Removes all elements from array that predicate returns truthy for
and returns an array of the removed elements. The predicate is invoked
with three arguments: (value, index, array).
Note: Unlike _.filter, this method mutates array. Use _.pull
to pull elements from an array by value.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to modify. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 2.0.0
Returns the new array of removed elements.
Example
var array = [1, 2, 3, 4];
var evens = _.remove(array, function(n) {
return n % 2 == 0;
});
console.log(array);
// => [1, 3]
console.log(evens);
// => [2, 4]
# static repeat(stringopt, nopt) → {string}
Repeats the given string n times.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to repeat. |
n |
number |
<optional> |
1 | The number of times to repeat the string. |
- Since:
- 3.0.0
Returns the repeated string.
Example
_.repeat('*', 3);
// => '***'
_.repeat('abc', 2);
// => 'abcabc'
_.repeat('abc', 0);
// => ''
# static repeat(stringopt, nopt) → {string}
Repeats the given string n times.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to repeat. |
n |
number |
<optional> |
1 | The number of times to repeat the string. |
- Since:
- 3.0.0
Returns the repeated string.
Example
_.repeat('*', 3);
// => '***'
_.repeat('abc', 2);
// => 'abcabc'
_.repeat('abc', 0);
// => ''
# static replace(stringopt, pattern, replacement) → {string}
Replaces matches for pattern in string with replacement.
Note: This method is based on
String#replace.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to modify. |
pattern |
RegExp | string | The pattern to replace. |
||
replacement |
function | string | The match replacement. |
- Since:
- 4.0.0
Returns the modified string.
Example
_.replace('Hi Fred', 'Fred', 'Barney');
// => 'Hi Barney'
# static replace(stringopt, pattern, replacement) → {string}
Replaces matches for pattern in string with replacement.
Note: This method is based on
String#replace.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to modify. |
pattern |
RegExp | string | The pattern to replace. |
||
replacement |
function | string | The match replacement. |
- Since:
- 4.0.0
Returns the modified string.
Example
_.replace('Hi Fred', 'Fred', 'Barney');
// => 'Hi Barney'
# static rest(func, startopt) → {function}
Creates a function that invokes func with the this binding of the
created function and arguments from start and beyond provided as
an array.
Note: This method is based on the rest parameter.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
function | The function to apply a rest parameter to. |
||
start |
number |
<optional> |
func.length-1 | The start position of the rest parameter. |
- Since:
- 4.0.0
Returns the new function.
Example
var say = _.rest(function(what, names) {
return what + ' ' + _.initial(names).join(', ') +
(_.size(names) > 1 ? ', & ' : '') + _.last(names);
});
say('hello', 'fred', 'barney', 'pebbles');
// => 'hello fred, barney, & pebbles'
# static rest(func, startopt) → {function}
Creates a function that invokes func with the this binding of the
created function and arguments from start and beyond provided as
an array.
Note: This method is based on the rest parameter.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
function | The function to apply a rest parameter to. |
||
start |
number |
<optional> |
func.length-1 | The start position of the rest parameter. |
- Since:
- 4.0.0
Returns the new function.
Example
var say = _.rest(function(what, names) {
return what + ' ' + _.initial(names).join(', ') +
(_.size(names) > 1 ? ', & ' : '') + _.last(names);
});
say('hello', 'fred', 'barney', 'pebbles');
// => 'hello fred, barney, & pebbles'
# static result(object, path, defaultValueopt) → {*}
This method is like _.get except that if the resolved value is a
function it's invoked with the this binding of its parent object and
its result is returned.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
object |
Object | The object to query. |
|
path |
Array | string | The path of the property to resolve. |
|
defaultValue |
* |
<optional> |
The value returned for |
- Since:
- 0.1.0
Returns the resolved value.
Example
var object = { 'a': [{ 'b': { 'c1': 3, 'c2': _.constant(4) } }] };
_.result(object, 'a[0].b.c1');
// => 3
_.result(object, 'a[0].b.c2');
// => 4
_.result(object, 'a[0].b.c3', 'default');
// => 'default'
_.result(object, 'a[0].b.c3', _.constant('default'));
// => 'default'
# static result(object, path, defaultValueopt) → {*}
This method is like _.get except that if the resolved value is a
function it's invoked with the this binding of its parent object and
its result is returned.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
object |
Object | The object to query. |
|
path |
Array | string | The path of the property to resolve. |
|
defaultValue |
* |
<optional> |
The value returned for |
- Since:
- 0.1.0
Returns the resolved value.
Example
var object = { 'a': [{ 'b': { 'c1': 3, 'c2': _.constant(4) } }] };
_.result(object, 'a[0].b.c1');
// => 3
_.result(object, 'a[0].b.c2');
// => 4
_.result(object, 'a[0].b.c3', 'default');
// => 'default'
_.result(object, 'a[0].b.c3', _.constant('default'));
// => 'default'
# static result(object, path, defaultValueopt) → {*}
This method is like _.get except that if the resolved value is a
function it's invoked with the this binding of its parent object and
its result is returned.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
object |
Object | The object to query. |
|
path |
Array | string | The path of the property to resolve. |
|
defaultValue |
* |
<optional> |
The value returned for |
- Since:
- 0.1.0
Returns the resolved value.
Example
var object = { 'a': [{ 'b': { 'c1': 3, 'c2': _.constant(4) } }] };
_.result(object, 'a[0].b.c1');
// => 3
_.result(object, 'a[0].b.c2');
// => 4
_.result(object, 'a[0].b.c3', 'default');
// => 'default'
_.result(object, 'a[0].b.c3', _.constant('default'));
// => 'default'
# static reverse(array) → {Array}
Reverses array so that the first element becomes the last, the second
element becomes the second to last, and so on.
Note: This method mutates array and is based on
Array#reverse.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to modify. |
- Since:
- 4.0.0
Returns array.
Example
var array = [1, 2, 3];
_.reverse(array);
// => [3, 2, 1]
console.log(array);
// => [3, 2, 1]
# static reverse(array) → {Array}
Reverses array so that the first element becomes the last, the second
element becomes the second to last, and so on.
Note: This method mutates array and is based on
Array#reverse.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to modify. |
- Since:
- 4.0.0
Returns array.
Example
var array = [1, 2, 3];
_.reverse(array);
// => [3, 2, 1]
console.log(array);
// => [3, 2, 1]
# static runInContext(contextopt) → {function}
Create a new pristine lodash function using the context object.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
context |
Object |
<optional> |
root | The context object. |
- Since:
- 1.1.0
Returns a new lodash function.
Example
_.mixin({ 'foo': _.constant('foo') });
var lodash = _.runInContext();
lodash.mixin({ 'bar': lodash.constant('bar') });
_.isFunction(_.foo);
// => true
_.isFunction(_.bar);
// => false
lodash.isFunction(lodash.foo);
// => false
lodash.isFunction(lodash.bar);
// => true
// Create a suped-up `defer` in Node.js.
var defer = _.runInContext({ 'setTimeout': setImmediate }).defer;
# static sample(collection) → {*}
Gets a random element from collection.
Parameters:
| Name | Type | Description |
|---|---|---|
collection |
Array | Object | The collection to sample. |
- Since:
- 2.0.0
Returns the random element.
Example
_.sample([1, 2, 3, 4]);
// => 2
# static sample(collection) → {*}
Gets a random element from collection.
Parameters:
| Name | Type | Description |
|---|---|---|
collection |
Array | Object | The collection to sample. |
- Since:
- 2.0.0
Returns the random element.
Example
_.sample([1, 2, 3, 4]);
// => 2
# static sampleSize(collection, nopt) → {Array}
Gets n random elements at unique keys from collection up to the
size of collection.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to sample. |
||
n |
number |
<optional> |
1 | The number of elements to sample. |
- Since:
- 4.0.0
Returns the random elements.
Example
_.sampleSize([1, 2, 3], 2);
// => [3, 1]
_.sampleSize([1, 2, 3], 4);
// => [2, 3, 1]
# static sampleSize(collection, nopt) → {Array}
Gets n random elements at unique keys from collection up to the
size of collection.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to sample. |
||
n |
number |
<optional> |
1 | The number of elements to sample. |
- Since:
- 4.0.0
Returns the random elements.
Example
_.sampleSize([1, 2, 3], 2);
// => [3, 1]
_.sampleSize([1, 2, 3], 4);
// => [2, 3, 1]
# static set(object, path, value) → {Object}
Sets the value at path of object. If a portion of path doesn't exist,
it's created. Arrays are created for missing index properties while objects
are created for all other missing properties. Use _.setWith to customize
path creation.
Note: This method mutates object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to modify. |
path |
Array | string | The path of the property to set. |
value |
* | The value to set. |
- Since:
- 3.7.0
Returns object.
Example
var object = { 'a': [{ 'b': { 'c': 3 } }] };
_.set(object, 'a[0].b.c', 4);
console.log(object.a[0].b.c);
// => 4
_.set(object, ['x', '0', 'y', 'z'], 5);
console.log(object.x[0].y.z);
// => 5
# static set(object, path, value) → {Object}
Sets the value at path of object. If a portion of path doesn't exist,
it's created. Arrays are created for missing index properties while objects
are created for all other missing properties. Use _.setWith to customize
path creation.
Note: This method mutates object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to modify. |
path |
Array | string | The path of the property to set. |
value |
* | The value to set. |
- Since:
- 3.7.0
Returns object.
Example
var object = { 'a': [{ 'b': { 'c': 3 } }] };
_.set(object, 'a[0].b.c', 4);
console.log(object.a[0].b.c);
// => 4
_.set(object, ['x', '0', 'y', 'z'], 5);
console.log(object.x[0].y.z);
// => 5
# static setCasperable(casperable) → {Datasource}
Set datasource casperable
Parameters:
| Name | Type | Description |
|---|---|---|
casperable |
# static setFrom(from) → {Datasource}
Set casperable from
Parameters:
| Name | Type | Description |
|---|---|---|
from |
# static setGroupedBy(groupedby) → {Datasource}
Set datasource groupedby
Parameters:
| Name | Type | Description |
|---|---|---|
groupedby |
# static setLimit(limit) → {Datasource}
Set datasource limit
Parameters:
| Name | Type | Description |
|---|---|---|
limit |
# static setPrecision(precision) → {Datasource}
Set datasource precision
Parameters:
| Name | Type | Description |
|---|---|---|
precision |
# static setSelect(select) → {Datasource}
Set datasource select
Parameters:
| Name | Type | Description |
|---|---|---|
select |
# static setSortScaleUp(isScaleUp) → {Datasource}
Set datasource isScaleUp
Parameters:
| Name | Type | Description |
|---|---|---|
isScaleUp |
# static setTimerange(timerange) → {Datasource}
Set datasource timerange
Parameters:
| Name | Type | Description |
|---|---|---|
timerange |
# static setWhere(where) → {Datasource}
Set datasource where
Parameters:
| Name | Type | Description |
|---|---|---|
where |
# static setWith(object, path, value, customizeropt) → {Object}
This method is like _.set except that it accepts customizer which is
invoked to produce the objects of path. If customizer returns undefined
path creation is handled by the method instead. The customizer is invoked
with three arguments: (nsValue, key, nsObject).
Note: This method mutates object.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
object |
Object | The object to modify. |
|
path |
Array | string | The path of the property to set. |
|
value |
* | The value to set. |
|
customizer |
function |
<optional> |
The function to customize assigned values. |
- Since:
- 4.0.0
Returns object.
Example
var object = {};
_.setWith(object, '[0][1]', 'a', Object);
// => { '0': { '1': 'a' } }
# static setWith(object, path, value, customizeropt) → {Object}
This method is like _.set except that it accepts customizer which is
invoked to produce the objects of path. If customizer returns undefined
path creation is handled by the method instead. The customizer is invoked
with three arguments: (nsValue, key, nsObject).
Note: This method mutates object.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
object |
Object | The object to modify. |
|
path |
Array | string | The path of the property to set. |
|
value |
* | The value to set. |
|
customizer |
function |
<optional> |
The function to customize assigned values. |
- Since:
- 4.0.0
Returns object.
Example
var object = {};
_.setWith(object, '[0][1]', 'a', Object);
// => { '0': { '1': 'a' } }
# static shuffle(collection) → {Array}
Creates an array of shuffled values, using a version of the Fisher-Yates shuffle.
Parameters:
| Name | Type | Description |
|---|---|---|
collection |
Array | Object | The collection to shuffle. |
- Since:
- 0.1.0
Returns the new shuffled array.
Example
_.shuffle([1, 2, 3, 4]);
// => [4, 1, 3, 2]
# static shuffle(collection) → {Array}
Creates an array of shuffled values, using a version of the Fisher-Yates shuffle.
Parameters:
| Name | Type | Description |
|---|---|---|
collection |
Array | Object | The collection to shuffle. |
- Since:
- 0.1.0
Returns the new shuffled array.
Example
_.shuffle([1, 2, 3, 4]);
// => [4, 1, 3, 2]
# static size(collection) → {number}
Gets the size of collection by returning its length for array-like
values or the number of own enumerable string keyed properties for objects.
Parameters:
| Name | Type | Description |
|---|---|---|
collection |
Array | Object | string | The collection to inspect. |
- Since:
- 0.1.0
Returns the collection size.
Example
_.size([1, 2, 3]);
// => 3
_.size({ 'a': 1, 'b': 2 });
// => 2
_.size('pebbles');
// => 7
# static size(collection) → {number}
Gets the size of collection by returning its length for array-like
values or the number of own enumerable string keyed properties for objects.
Parameters:
| Name | Type | Description |
|---|---|---|
collection |
Array | Object | string | The collection to inspect. |
- Since:
- 0.1.0
Returns the collection size.
Example
_.size([1, 2, 3]);
// => 3
_.size({ 'a': 1, 'b': 2 });
// => 2
_.size('pebbles');
// => 7
# static size(collection) → {number}
Gets the size of collection by returning its length for array-like
values or the number of own enumerable string keyed properties for objects.
Parameters:
| Name | Type | Description |
|---|---|---|
collection |
Array | Object | string | The collection to inspect. |
- Since:
- 0.1.0
Returns the collection size.
Example
_.size([1, 2, 3]);
// => 3
_.size({ 'a': 1, 'b': 2 });
// => 2
_.size('pebbles');
// => 7
# static slice(array, startopt, endopt) → {Array}
Creates a slice of array from start up to, but not including, end.
Note: This method is used instead of
Array#slice to ensure dense arrays are
returned.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to slice. |
||
start |
number |
<optional> |
0 | The start position. |
end |
number |
<optional> |
array.length | The end position. |
- Since:
- 3.0.0
Returns the slice of array.
# static slice(array, startopt, endopt) → {Array}
Creates a slice of array from start up to, but not including, end.
Note: This method is used instead of
Array#slice to ensure dense arrays are
returned.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to slice. |
||
start |
number |
<optional> |
0 | The start position. |
end |
number |
<optional> |
array.length | The end position. |
- Since:
- 3.0.0
Returns the slice of array.
# static slice(array, startopt, endopt) → {Array}
Creates a slice of array from start up to, but not including, end.
Note: This method is used instead of
Array#slice to ensure dense arrays are
returned.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to slice. |
||
start |
number |
<optional> |
0 | The start position. |
end |
number |
<optional> |
array.length | The end position. |
- Since:
- 3.0.0
Returns the slice of array.
# static some(collection, predicateopt) → {boolean}
Checks if predicate returns truthy for any element of collection.
Iteration is stopped once predicate returns truthy. The predicate is
invoked with three arguments: (value, index|key, collection).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
Returns true if any element passes the predicate check,
else false.
Example
_.some([null, 0, 'yes', false], Boolean);
// => true
var users = [
{ 'user': 'barney', 'active': true },
{ 'user': 'fred', 'active': false }
];
// The `_.matches` iteratee shorthand.
_.some(users, { 'user': 'barney', 'active': false });
// => false
// The `_.matchesProperty` iteratee shorthand.
_.some(users, ['active', false]);
// => true
// The `_.property` iteratee shorthand.
_.some(users, 'active');
// => true
# static some(collection, predicateopt) → {boolean}
Checks if predicate returns truthy for any element of collection.
Iteration is stopped once predicate returns truthy. The predicate is
invoked with three arguments: (value, index|key, collection).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
Returns true if any element passes the predicate check,
else false.
Example
_.some([null, 0, 'yes', false], Boolean);
// => true
var users = [
{ 'user': 'barney', 'active': true },
{ 'user': 'fred', 'active': false }
];
// The `_.matches` iteratee shorthand.
_.some(users, { 'user': 'barney', 'active': false });
// => false
// The `_.matchesProperty` iteratee shorthand.
_.some(users, ['active', false]);
// => true
// The `_.property` iteratee shorthand.
_.some(users, 'active');
// => true
# static some(collection, predicateopt) → {boolean}
Checks if predicate returns truthy for any element of collection.
Iteration is stopped once predicate returns truthy. The predicate is
invoked with three arguments: (value, index|key, collection).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
Returns true if any element passes the predicate check,
else false.
Example
_.some([null, 0, 'yes', false], Boolean);
// => true
var users = [
{ 'user': 'barney', 'active': true },
{ 'user': 'fred', 'active': false }
];
// The `_.matches` iteratee shorthand.
_.some(users, { 'user': 'barney', 'active': false });
// => false
// The `_.matchesProperty` iteratee shorthand.
_.some(users, ['active', false]);
// => true
// The `_.property` iteratee shorthand.
_.some(users, 'active');
// => true
# static sortBy(collection, …iterateesopt) → {Array}
Creates an array of elements, sorted in ascending order by the results of running each element in a collection thru each iteratee. This method performs a stable sort, that is, it preserves the original sort order of equal elements. The iteratees are invoked with one argument: (value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
collection |
Array | Object | The collection to iterate over. |
||
iteratees |
function | Array.<function()> |
<optional> <repeatable> |
[_.identity] | The iteratees to sort by. |
- Since:
- 0.1.0
Returns the new sorted array.
Example
var users = [
{ 'user': 'fred', 'age': 48 },
{ 'user': 'barney', 'age': 36 },
{ 'user': 'fred', 'age': 30 },
{ 'user': 'barney', 'age': 34 }
];
_.sortBy(users, [function(o) { return o.user; }]);
// => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 30]]
_.sortBy(users, ['user', 'age']);
// => objects for [['barney', 34], ['barney', 36], ['fred', 30], ['fred', 48]]
# static sortedIndex(array, value) → {number}
Uses a binary search to determine the lowest index at which value
should be inserted into array in order to maintain its sort order.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The sorted array to inspect. |
value |
* | The value to evaluate. |
- Since:
- 0.1.0
Returns the index at which value should be inserted
into array.
Example
_.sortedIndex([30, 50], 40);
// => 1
# static sortedIndex(array, value) → {number}
Uses a binary search to determine the lowest index at which value
should be inserted into array in order to maintain its sort order.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The sorted array to inspect. |
value |
* | The value to evaluate. |
- Since:
- 0.1.0
Returns the index at which value should be inserted
into array.
Example
_.sortedIndex([30, 50], 40);
// => 1
# static sortedIndexBy(array, value, iterateeopt) → {number}
This method is like _.sortedIndex except that it accepts iteratee
which is invoked for value and each element of array to compute their
sort ranking. The iteratee is invoked with one argument: (value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The sorted array to inspect. |
||
value |
* | The value to evaluate. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.0.0
Returns the index at which value should be inserted
into array.
Example
var objects = [{ 'x': 4 }, { 'x': 5 }];
_.sortedIndexBy(objects, { 'x': 4 }, function(o) { return o.x; });
// => 0
// The `_.property` iteratee shorthand.
_.sortedIndexBy(objects, { 'x': 4 }, 'x');
// => 0
# static sortedIndexBy(array, value, iterateeopt) → {number}
This method is like _.sortedIndex except that it accepts iteratee
which is invoked for value and each element of array to compute their
sort ranking. The iteratee is invoked with one argument: (value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The sorted array to inspect. |
||
value |
* | The value to evaluate. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.0.0
Returns the index at which value should be inserted
into array.
Example
var objects = [{ 'x': 4 }, { 'x': 5 }];
_.sortedIndexBy(objects, { 'x': 4 }, function(o) { return o.x; });
// => 0
// The `_.property` iteratee shorthand.
_.sortedIndexBy(objects, { 'x': 4 }, 'x');
// => 0
# static sortedIndexOf(array, value) → {number}
This method is like _.indexOf except that it performs a binary
search on a sorted array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to inspect. |
value |
* | The value to search for. |
- Since:
- 4.0.0
Returns the index of the matched value, else -1.
Example
_.sortedIndexOf([4, 5, 5, 5, 6], 5);
// => 1
# static sortedIndexOf(array, value) → {number}
This method is like _.indexOf except that it performs a binary
search on a sorted array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to inspect. |
value |
* | The value to search for. |
- Since:
- 4.0.0
Returns the index of the matched value, else -1.
Example
_.sortedIndexOf([4, 5, 5, 5, 6], 5);
// => 1
# static sortedLastIndex(array, value) → {number}
This method is like _.sortedIndex except that it returns the highest
index at which value should be inserted into array in order to
maintain its sort order.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The sorted array to inspect. |
value |
* | The value to evaluate. |
- Since:
- 3.0.0
Returns the index at which value should be inserted
into array.
Example
_.sortedLastIndex([4, 5, 5, 5, 6], 5);
// => 4
# static sortedLastIndex(array, value) → {number}
This method is like _.sortedIndex except that it returns the highest
index at which value should be inserted into array in order to
maintain its sort order.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The sorted array to inspect. |
value |
* | The value to evaluate. |
- Since:
- 3.0.0
Returns the index at which value should be inserted
into array.
Example
_.sortedLastIndex([4, 5, 5, 5, 6], 5);
// => 4
# static sortedLastIndexBy(array, value, iterateeopt) → {number}
This method is like _.sortedLastIndex except that it accepts iteratee
which is invoked for value and each element of array to compute their
sort ranking. The iteratee is invoked with one argument: (value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The sorted array to inspect. |
||
value |
* | The value to evaluate. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.0.0
Returns the index at which value should be inserted
into array.
Example
var objects = [{ 'x': 4 }, { 'x': 5 }];
_.sortedLastIndexBy(objects, { 'x': 4 }, function(o) { return o.x; });
// => 1
// The `_.property` iteratee shorthand.
_.sortedLastIndexBy(objects, { 'x': 4 }, 'x');
// => 1
# static sortedLastIndexBy(array, value, iterateeopt) → {number}
This method is like _.sortedLastIndex except that it accepts iteratee
which is invoked for value and each element of array to compute their
sort ranking. The iteratee is invoked with one argument: (value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The sorted array to inspect. |
||
value |
* | The value to evaluate. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.0.0
View Source node_modules/lodash/sortedLastIndexBy.js, line 29
Returns the index at which value should be inserted
into array.
Example
var objects = [{ 'x': 4 }, { 'x': 5 }];
_.sortedLastIndexBy(objects, { 'x': 4 }, function(o) { return o.x; });
// => 1
// The `_.property` iteratee shorthand.
_.sortedLastIndexBy(objects, { 'x': 4 }, 'x');
// => 1
# static sortedLastIndexOf(array, value) → {number}
This method is like _.lastIndexOf except that it performs a binary
search on a sorted array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to inspect. |
value |
* | The value to search for. |
- Since:
- 4.0.0
Returns the index of the matched value, else -1.
Example
_.sortedLastIndexOf([4, 5, 5, 5, 6], 5);
// => 3
# static sortedLastIndexOf(array, value) → {number}
This method is like _.lastIndexOf except that it performs a binary
search on a sorted array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to inspect. |
value |
* | The value to search for. |
- Since:
- 4.0.0
View Source node_modules/lodash/sortedLastIndexOf.js, line 20
Returns the index of the matched value, else -1.
Example
_.sortedLastIndexOf([4, 5, 5, 5, 6], 5);
// => 3
# static sortedUniq(array) → {Array}
This method is like _.uniq except that it's designed and optimized
for sorted arrays.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to inspect. |
- Since:
- 4.0.0
Returns the new duplicate free array.
Example
_.sortedUniq([1, 1, 2]);
// => [1, 2]
# static sortedUniq(array) → {Array}
This method is like _.uniq except that it's designed and optimized
for sorted arrays.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to inspect. |
- Since:
- 4.0.0
Returns the new duplicate free array.
Example
_.sortedUniq([1, 1, 2]);
// => [1, 2]
# static sortedUniqBy(array, iterateeopt) → {Array}
This method is like _.uniqBy except that it's designed and optimized
for sorted arrays.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
array |
Array | The array to inspect. |
|
iteratee |
function |
<optional> |
The iteratee invoked per element. |
- Since:
- 4.0.0
Returns the new duplicate free array.
Example
_.sortedUniqBy([1.1, 1.2, 2.3, 2.4], Math.floor);
// => [1.1, 2.3]
# static sortedUniqBy(array, iterateeopt) → {Array}
This method is like _.uniqBy except that it's designed and optimized
for sorted arrays.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
array |
Array | The array to inspect. |
|
iteratee |
function |
<optional> |
The iteratee invoked per element. |
- Since:
- 4.0.0
Returns the new duplicate free array.
Example
_.sortedUniqBy([1.1, 1.2, 2.3, 2.4], Math.floor);
// => [1.1, 2.3]
# static split(stringopt, separator, limitopt) → {Array}
Splits string by separator.
Note: This method is based on
String#split.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to split. |
separator |
RegExp | string | The separator pattern to split by. |
||
limit |
number |
<optional> |
The length to truncate results to. |
- Since:
- 4.0.0
Returns the string segments.
Example
_.split('a-b-c', '-', 2);
// => ['a', 'b']
# static split(stringopt, separator, limitopt) → {Array}
Splits string by separator.
Note: This method is based on
String#split.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to split. |
separator |
RegExp | string | The separator pattern to split by. |
||
limit |
number |
<optional> |
The length to truncate results to. |
- Since:
- 4.0.0
Returns the string segments.
Example
_.split('a-b-c', '-', 2);
// => ['a', 'b']
# static spread(func, startopt) → {function}
Creates a function that invokes func with the this binding of the
create function and an array of arguments much like
Function#apply.
Note: This method is based on the spread operator.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
function | The function to spread arguments over. |
||
start |
number |
<optional> |
0 | The start position of the spread. |
- Since:
- 3.2.0
Returns the new function.
Example
var say = _.spread(function(who, what) {
return who + ' says ' + what;
});
say(['fred', 'hello']);
// => 'fred says hello'
var numbers = Promise.all([
Promise.resolve(40),
Promise.resolve(36)
]);
numbers.then(_.spread(function(x, y) {
return x + y;
}));
// => a Promise of 76
# static spread(func, startopt) → {function}
Creates a function that invokes func with the this binding of the
create function and an array of arguments much like
Function#apply.
Note: This method is based on the spread operator.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
function | The function to spread arguments over. |
||
start |
number |
<optional> |
0 | The start position of the spread. |
- Since:
- 3.2.0
Returns the new function.
Example
var say = _.spread(function(who, what) {
return who + ' says ' + what;
});
say(['fred', 'hello']);
// => 'fred says hello'
var numbers = Promise.all([
Promise.resolve(40),
Promise.resolve(36)
]);
numbers.then(_.spread(function(x, y) {
return x + y;
}));
// => a Promise of 76
# static startsWith(stringopt, targetopt, positionopt) → {boolean}
Checks if string starts with the given target string.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to inspect. |
target |
string |
<optional> |
The string to search for. |
|
position |
number |
<optional> |
0 | The position to search from. |
- Since:
- 3.0.0
Returns true if string starts with target,
else false.
Example
_.startsWith('abc', 'a');
// => true
_.startsWith('abc', 'b');
// => false
_.startsWith('abc', 'b', 1);
// => true
# static startsWith(stringopt, targetopt, positionopt) → {boolean}
Checks if string starts with the given target string.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to inspect. |
target |
string |
<optional> |
The string to search for. |
|
position |
number |
<optional> |
0 | The position to search from. |
- Since:
- 3.0.0
Returns true if string starts with target,
else false.
Example
_.startsWith('abc', 'a');
// => true
_.startsWith('abc', 'b');
// => false
_.startsWith('abc', 'b', 1);
// => true
# static stubArray() → {Array}
This method returns a new empty array.
- Since:
- 4.13.0
Returns the new empty array.
Example
var arrays = _.times(2, _.stubArray);
console.log(arrays);
// => [[], []]
console.log(arrays[0] === arrays[1]);
// => false
# static stubArray() → {Array}
This method returns a new empty array.
- Since:
- 4.13.0
Returns the new empty array.
Example
var arrays = _.times(2, _.stubArray);
console.log(arrays);
// => [[], []]
console.log(arrays[0] === arrays[1]);
// => false
# static stubFalse() → {boolean}
This method returns false.
- Since:
- 4.13.0
Returns false.
Example
_.times(2, _.stubFalse);
// => [false, false]
# static stubFalse() → {boolean}
This method returns false.
- Since:
- 4.13.0
Returns false.
Example
_.times(2, _.stubFalse);
// => [false, false]
# static stubObject() → {Object}
This method returns a new empty object.
- Since:
- 4.13.0
Returns the new empty object.
Example
var objects = _.times(2, _.stubObject);
console.log(objects);
// => [{}, {}]
console.log(objects[0] === objects[1]);
// => false
# static stubObject() → {Object}
This method returns a new empty object.
- Since:
- 4.13.0
Returns the new empty object.
Example
var objects = _.times(2, _.stubObject);
console.log(objects);
// => [{}, {}]
console.log(objects[0] === objects[1]);
// => false
# static stubString() → {string}
This method returns an empty string.
- Since:
- 4.13.0
Returns the empty string.
Example
_.times(2, _.stubString);
// => ['', '']
# static stubString() → {string}
This method returns an empty string.
- Since:
- 4.13.0
Returns the empty string.
Example
_.times(2, _.stubString);
// => ['', '']
# static stubTrue() → {boolean}
This method returns true.
- Since:
- 4.13.0
Returns true.
Example
_.times(2, _.stubTrue);
// => [true, true]
# static stubTrue() → {boolean}
This method returns true.
- Since:
- 4.13.0
Returns true.
Example
_.times(2, _.stubTrue);
// => [true, true]
# static sum(array) → {number}
Computes the sum of the values in array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to iterate over. |
- Since:
- 3.4.0
Returns the sum.
Example
_.sum([4, 2, 8, 6]);
// => 20
# static sum(array) → {number}
Computes the sum of the values in array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to iterate over. |
- Since:
- 3.4.0
Returns the sum.
Example
_.sum([4, 2, 8, 6]);
// => 20
# static sumBy(array, iterateeopt) → {number}
This method is like _.sum except that it accepts iteratee which is
invoked for each element in array to generate the value to be summed.
The iteratee is invoked with one argument: (value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.0.0
Returns the sum.
Example
var objects = [{ 'n': 4 }, { 'n': 2 }, { 'n': 8 }, { 'n': 6 }];
_.sumBy(objects, function(o) { return o.n; });
// => 20
// The `_.property` iteratee shorthand.
_.sumBy(objects, 'n');
// => 20
# static sumBy(array, iterateeopt) → {number}
This method is like _.sum except that it accepts iteratee which is
invoked for each element in array to generate the value to be summed.
The iteratee is invoked with one argument: (value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.0.0
Returns the sum.
Example
var objects = [{ 'n': 4 }, { 'n': 2 }, { 'n': 8 }, { 'n': 6 }];
_.sumBy(objects, function(o) { return o.n; });
// => 20
// The `_.property` iteratee shorthand.
_.sumBy(objects, 'n');
// => 20
# static tail(array) → {Array}
Gets all but the first element of array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to query. |
- Since:
- 4.0.0
Returns the slice of array.
Example
_.tail([1, 2, 3]);
// => [2, 3]
# static tail(array) → {Array}
Gets all but the first element of array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to query. |
- Since:
- 4.0.0
Returns the slice of array.
Example
_.tail([1, 2, 3]);
// => [2, 3]
# static take(array, nopt) → {Array}
Creates a slice of array with n elements taken from the beginning.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
n |
number |
<optional> |
1 | The number of elements to take. |
- Since:
- 0.1.0
Returns the slice of array.
Example
_.take([1, 2, 3]);
// => [1]
_.take([1, 2, 3], 2);
// => [1, 2]
_.take([1, 2, 3], 5);
// => [1, 2, 3]
_.take([1, 2, 3], 0);
// => []
# static take(array, nopt) → {Array}
Creates a slice of array with n elements taken from the beginning.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
n |
number |
<optional> |
1 | The number of elements to take. |
- Since:
- 0.1.0
Returns the slice of array.
Example
_.take([1, 2, 3]);
// => [1]
_.take([1, 2, 3], 2);
// => [1, 2]
_.take([1, 2, 3], 5);
// => [1, 2, 3]
_.take([1, 2, 3], 0);
// => []
# static takeRight(array, nopt) → {Array}
Creates a slice of array with n elements taken from the end.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
n |
number |
<optional> |
1 | The number of elements to take. |
- Since:
- 3.0.0
Returns the slice of array.
Example
_.takeRight([1, 2, 3]);
// => [3]
_.takeRight([1, 2, 3], 2);
// => [2, 3]
_.takeRight([1, 2, 3], 5);
// => [1, 2, 3]
_.takeRight([1, 2, 3], 0);
// => []
# static takeRight(array, nopt) → {Array}
Creates a slice of array with n elements taken from the end.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
n |
number |
<optional> |
1 | The number of elements to take. |
- Since:
- 3.0.0
Returns the slice of array.
Example
_.takeRight([1, 2, 3]);
// => [3]
_.takeRight([1, 2, 3], 2);
// => [2, 3]
_.takeRight([1, 2, 3], 5);
// => [1, 2, 3]
_.takeRight([1, 2, 3], 0);
// => []
# static takeRightWhile(array, predicateopt) → {Array}
Creates a slice of array with elements taken from the end. Elements are
taken until predicate returns falsey. The predicate is invoked with
three arguments: (value, index, array).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 3.0.0
Returns the slice of array.
Example
var users = [
{ 'user': 'barney', 'active': true },
{ 'user': 'fred', 'active': false },
{ 'user': 'pebbles', 'active': false }
];
_.takeRightWhile(users, function(o) { return !o.active; });
// => objects for ['fred', 'pebbles']
// The `_.matches` iteratee shorthand.
_.takeRightWhile(users, { 'user': 'pebbles', 'active': false });
// => objects for ['pebbles']
// The `_.matchesProperty` iteratee shorthand.
_.takeRightWhile(users, ['active', false]);
// => objects for ['fred', 'pebbles']
// The `_.property` iteratee shorthand.
_.takeRightWhile(users, 'active');
// => []
# static takeRightWhile(array, predicateopt) → {Array}
Creates a slice of array with elements taken from the end. Elements are
taken until predicate returns falsey. The predicate is invoked with
three arguments: (value, index, array).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 3.0.0
Returns the slice of array.
Example
var users = [
{ 'user': 'barney', 'active': true },
{ 'user': 'fred', 'active': false },
{ 'user': 'pebbles', 'active': false }
];
_.takeRightWhile(users, function(o) { return !o.active; });
// => objects for ['fred', 'pebbles']
// The `_.matches` iteratee shorthand.
_.takeRightWhile(users, { 'user': 'pebbles', 'active': false });
// => objects for ['pebbles']
// The `_.matchesProperty` iteratee shorthand.
_.takeRightWhile(users, ['active', false]);
// => objects for ['fred', 'pebbles']
// The `_.property` iteratee shorthand.
_.takeRightWhile(users, 'active');
// => []
# static takeWhile(array, predicateopt) → {Array}
Creates a slice of array with elements taken from the beginning. Elements
are taken until predicate returns falsey. The predicate is invoked with
three arguments: (value, index, array).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 3.0.0
Returns the slice of array.
Example
var users = [
{ 'user': 'barney', 'active': false },
{ 'user': 'fred', 'active': false },
{ 'user': 'pebbles', 'active': true }
];
_.takeWhile(users, function(o) { return !o.active; });
// => objects for ['barney', 'fred']
// The `_.matches` iteratee shorthand.
_.takeWhile(users, { 'user': 'barney', 'active': false });
// => objects for ['barney']
// The `_.matchesProperty` iteratee shorthand.
_.takeWhile(users, ['active', false]);
// => objects for ['barney', 'fred']
// The `_.property` iteratee shorthand.
_.takeWhile(users, 'active');
// => []
# static takeWhile(array, predicateopt) → {Array}
Creates a slice of array with elements taken from the beginning. Elements
are taken until predicate returns falsey. The predicate is invoked with
three arguments: (value, index, array).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to query. |
||
predicate |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 3.0.0
Returns the slice of array.
Example
var users = [
{ 'user': 'barney', 'active': false },
{ 'user': 'fred', 'active': false },
{ 'user': 'pebbles', 'active': true }
];
_.takeWhile(users, function(o) { return !o.active; });
// => objects for ['barney', 'fred']
// The `_.matches` iteratee shorthand.
_.takeWhile(users, { 'user': 'barney', 'active': false });
// => objects for ['barney']
// The `_.matchesProperty` iteratee shorthand.
_.takeWhile(users, ['active', false]);
// => objects for ['barney', 'fred']
// The `_.property` iteratee shorthand.
_.takeWhile(users, 'active');
// => []
# static tap(value, interceptor) → {*}
This method invokes interceptor and returns value. The interceptor
is invoked with one argument; (value). The purpose of this method is to
"tap into" a method chain sequence in order to modify intermediate results.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to provide to |
interceptor |
function | The function to invoke. |
- Since:
- 0.1.0
Returns value.
Example
_([1, 2, 3])
.tap(function(array) {
// Mutate input array.
array.pop();
})
.reverse()
.value();
// => [2, 1]
# static tap(value, interceptor) → {*}
This method invokes interceptor and returns value. The interceptor
is invoked with one argument; (value). The purpose of this method is to
"tap into" a method chain sequence in order to modify intermediate results.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to provide to |
interceptor |
function | The function to invoke. |
- Since:
- 0.1.0
Returns value.
Example
_([1, 2, 3])
.tap(function(array) {
// Mutate input array.
array.pop();
})
.reverse()
.value();
// => [2, 1]
# static tap(value, interceptor) → {*}
This method invokes interceptor and returns value. The interceptor
is invoked with one argument; (value). The purpose of this method is to
"tap into" a method chain sequence in order to modify intermediate results.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to provide to |
interceptor |
function | The function to invoke. |
- Since:
- 0.1.0
Returns value.
Example
_([1, 2, 3])
.tap(function(array) {
// Mutate input array.
array.pop();
})
.reverse()
.value();
// => [2, 1]
# static template(stringopt, optionsopt) → {function}
Creates a compiled template function that can interpolate data properties
in "interpolate" delimiters, HTML-escape interpolated data properties in
"escape" delimiters, and execute JavaScript in "evaluate" delimiters. Data
properties may be accessed as free variables in the template. If a setting
object is given, it takes precedence over _.templateSettings values.
Note: In the development build _.template utilizes
sourceURLs
for easier debugging.
For more information on precompiling templates see lodash's custom builds documentation.
For more information on Chrome extension sandboxes see Chrome's extensions documentation.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The template string. |
options |
Object |
<optional> |
{} | The options object. |
escape |
RegExp |
<optional> |
_.templateSettings.escape | The HTML "escape" delimiter. |
evaluate |
RegExp |
<optional> |
_.templateSettings.evaluate | The "evaluate" delimiter. |
imports |
Object |
<optional> |
_.templateSettings.imports | An object to import into the template as free variables. |
interpolate |
RegExp |
<optional> |
_.templateSettings.interpolate | The "interpolate" delimiter. |
sourceURL |
string |
<optional> |
'lodash.templateSources[n]' | The sourceURL of the compiled template. |
variable |
string |
<optional> |
'obj' | The data object variable name. |
- Since:
- 0.1.0
Returns the compiled template function.
Example
// Use the "interpolate" delimiter to create a compiled template.
var compiled = _.template('hello <%= user %>!');
compiled({ 'user': 'fred' });
// => 'hello fred!'
// Use the HTML "escape" delimiter to escape data property values.
var compiled = _.template('<b><%- value %></b>');
compiled({ 'value': '<script>' });
// => '<b><script></b>'
// Use the "evaluate" delimiter to execute JavaScript and generate HTML.
var compiled = _.template('<% _.forEach(users, function(user) { %><li><%- user %></li><% }); %>');
compiled({ 'users': ['fred', 'barney'] });
// => '<li>fred</li><li>barney</li>'
// Use the internal `print` function in "evaluate" delimiters.
var compiled = _.template('<% print("hello " + user); %>!');
compiled({ 'user': 'barney' });
// => 'hello barney!'
// Use the ES template literal delimiter as an "interpolate" delimiter.
// Disable support by replacing the "interpolate" delimiter.
var compiled = _.template('hello ${ user }!');
compiled({ 'user': 'pebbles' });
// => 'hello pebbles!'
// Use backslashes to treat delimiters as plain text.
var compiled = _.template('<%= "\\<%- value %\\>" %>');
compiled({ 'value': 'ignored' });
// => '<%- value %>'
// Use the `imports` option to import `jQuery` as `jq`.
var text = '<% jq.each(users, function(user) { %><li><%- user %></li><% }); %>';
var compiled = _.template(text, { 'imports': { 'jq': jQuery } });
compiled({ 'users': ['fred', 'barney'] });
// => '<li>fred</li><li>barney</li>'
// Use the `sourceURL` option to specify a custom sourceURL for the template.
var compiled = _.template('hello <%= user %>!', { 'sourceURL': '/basic/greeting.jst' });
compiled(data);
// => Find the source of "greeting.jst" under the Sources tab or Resources panel of the web inspector.
// Use the `variable` option to ensure a with-statement isn't used in the compiled template.
var compiled = _.template('hi <%= data.user %>!', { 'variable': 'data' });
compiled.source;
// => function(data) {
// var __t, __p = '';
// __p += 'hi ' + ((__t = ( data.user )) == null ? '' : __t) + '!';
// return __p;
// }
// Use custom template delimiters.
_.templateSettings.interpolate = /{{([\s\S]+?)}}/g;
var compiled = _.template('hello {{ user }}!');
compiled({ 'user': 'mustache' });
// => 'hello mustache!'
// Use the `source` property to inline compiled templates for meaningful
// line numbers in error messages and stack traces.
fs.writeFileSync(path.join(process.cwd(), 'jst.js'), '\
var JST = {\
"main": ' + _.template(mainText).source + '\
};\
');
# static template(stringopt, optionsopt) → {function}
Creates a compiled template function that can interpolate data properties
in "interpolate" delimiters, HTML-escape interpolated data properties in
"escape" delimiters, and execute JavaScript in "evaluate" delimiters. Data
properties may be accessed as free variables in the template. If a setting
object is given, it takes precedence over _.templateSettings values.
Note: In the development build _.template utilizes
sourceURLs
for easier debugging.
For more information on precompiling templates see lodash's custom builds documentation.
For more information on Chrome extension sandboxes see Chrome's extensions documentation.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The template string. |
options |
Object |
<optional> |
{} | The options object. |
escape |
RegExp |
<optional> |
_.templateSettings.escape | The HTML "escape" delimiter. |
evaluate |
RegExp |
<optional> |
_.templateSettings.evaluate | The "evaluate" delimiter. |
imports |
Object |
<optional> |
_.templateSettings.imports | An object to import into the template as free variables. |
interpolate |
RegExp |
<optional> |
_.templateSettings.interpolate | The "interpolate" delimiter. |
sourceURL |
string |
<optional> |
'templateSources[n]' | The sourceURL of the compiled template. |
variable |
string |
<optional> |
'obj' | The data object variable name. |
- Since:
- 0.1.0
Returns the compiled template function.
Example
// Use the "interpolate" delimiter to create a compiled template.
var compiled = _.template('hello <%= user %>!');
compiled({ 'user': 'fred' });
// => 'hello fred!'
// Use the HTML "escape" delimiter to escape data property values.
var compiled = _.template('<b><%- value %></b>');
compiled({ 'value': '<script>' });
// => '<b><script></b>'
// Use the "evaluate" delimiter to execute JavaScript and generate HTML.
var compiled = _.template('<% _.forEach(users, function(user) { %><li><%- user %></li><% }); %>');
compiled({ 'users': ['fred', 'barney'] });
// => '<li>fred</li><li>barney</li>'
// Use the internal `print` function in "evaluate" delimiters.
var compiled = _.template('<% print("hello " + user); %>!');
compiled({ 'user': 'barney' });
// => 'hello barney!'
// Use the ES template literal delimiter as an "interpolate" delimiter.
// Disable support by replacing the "interpolate" delimiter.
var compiled = _.template('hello ${ user }!');
compiled({ 'user': 'pebbles' });
// => 'hello pebbles!'
// Use backslashes to treat delimiters as plain text.
var compiled = _.template('<%= "\\<%- value %\\>" %>');
compiled({ 'value': 'ignored' });
// => '<%- value %>'
// Use the `imports` option to import `jQuery` as `jq`.
var text = '<% jq.each(users, function(user) { %><li><%- user %></li><% }); %>';
var compiled = _.template(text, { 'imports': { 'jq': jQuery } });
compiled({ 'users': ['fred', 'barney'] });
// => '<li>fred</li><li>barney</li>'
// Use the `sourceURL` option to specify a custom sourceURL for the template.
var compiled = _.template('hello <%= user %>!', { 'sourceURL': '/basic/greeting.jst' });
compiled(data);
// => Find the source of "greeting.jst" under the Sources tab or Resources panel of the web inspector.
// Use the `variable` option to ensure a with-statement isn't used in the compiled template.
var compiled = _.template('hi <%= data.user %>!', { 'variable': 'data' });
compiled.source;
// => function(data) {
// var __t, __p = '';
// __p += 'hi ' + ((__t = ( data.user )) == null ? '' : __t) + '!';
// return __p;
// }
// Use custom template delimiters.
_.templateSettings.interpolate = /{{([\s\S]+?)}}/g;
var compiled = _.template('hello {{ user }}!');
compiled({ 'user': 'mustache' });
// => 'hello mustache!'
// Use the `source` property to inline compiled templates for meaningful
// line numbers in error messages and stack traces.
fs.writeFileSync(path.join(process.cwd(), 'jst.js'), '\
var JST = {\
"main": ' + _.template(mainText).source + '\
};\
');
# static throttle(func, waitopt, optionsopt) → {function}
Creates a throttled function that only invokes func at most once per
every wait milliseconds. The throttled function comes with a cancel
method to cancel delayed func invocations and a flush method to
immediately invoke them. Provide options to indicate whether func
should be invoked on the leading and/or trailing edge of the wait
timeout. The func is invoked with the last arguments provided to the
throttled function. Subsequent calls to the throttled function return the
result of the last func invocation.
Note: If leading and trailing options are true, func is
invoked on the trailing edge of the timeout only if the throttled function
is invoked more than once during the wait timeout.
If wait is 0 and leading is false, func invocation is deferred
until to the next tick, similar to setTimeout with a timeout of 0.
See David Corbacho's article
for details over the differences between _.throttle and _.debounce.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
function | The function to throttle. |
||
wait |
number |
<optional> |
0 | The number of milliseconds to throttle invocations to. |
options |
Object |
<optional> |
{} | The options object. |
leading |
boolean |
<optional> |
true | Specify invoking on the leading edge of the timeout. |
trailing |
boolean |
<optional> |
true | Specify invoking on the trailing edge of the timeout. |
- Since:
- 0.1.0
Returns the new throttled function.
Example
// Avoid excessively updating the position while scrolling.
jQuery(window).on('scroll', _.throttle(updatePosition, 100));
// Invoke `renewToken` when the click event is fired, but not more than once every 5 minutes.
var throttled = _.throttle(renewToken, 300000, { 'trailing': false });
jQuery(element).on('click', throttled);
// Cancel the trailing throttled invocation.
jQuery(window).on('popstate', throttled.cancel);
# static throttle(func, waitopt, optionsopt) → {function}
Creates a throttled function that only invokes func at most once per
every wait milliseconds. The throttled function comes with a cancel
method to cancel delayed func invocations and a flush method to
immediately invoke them. Provide options to indicate whether func
should be invoked on the leading and/or trailing edge of the wait
timeout. The func is invoked with the last arguments provided to the
throttled function. Subsequent calls to the throttled function return the
result of the last func invocation.
Note: If leading and trailing options are true, func is
invoked on the trailing edge of the timeout only if the throttled function
is invoked more than once during the wait timeout.
If wait is 0 and leading is false, func invocation is deferred
until to the next tick, similar to setTimeout with a timeout of 0.
See David Corbacho's article
for details over the differences between _.throttle and _.debounce.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
func |
function | The function to throttle. |
||
wait |
number |
<optional> |
0 | The number of milliseconds to throttle invocations to. |
options |
Object |
<optional> |
{} | The options object. |
leading |
boolean |
<optional> |
true | Specify invoking on the leading edge of the timeout. |
trailing |
boolean |
<optional> |
true | Specify invoking on the trailing edge of the timeout. |
- Since:
- 0.1.0
Returns the new throttled function.
Example
// Avoid excessively updating the position while scrolling.
jQuery(window).on('scroll', _.throttle(updatePosition, 100));
// Invoke `renewToken` when the click event is fired, but not more than once every 5 minutes.
var throttled = _.throttle(renewToken, 300000, { 'trailing': false });
jQuery(element).on('click', throttled);
// Cancel the trailing throttled invocation.
jQuery(window).on('popstate', throttled.cancel);
# static thru(value, interceptor) → {*}
This method is like _.tap except that it returns the result of interceptor.
The purpose of this method is to "pass thru" values replacing intermediate
results in a method chain sequence.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to provide to |
interceptor |
function | The function to invoke. |
- Since:
- 3.0.0
Returns the result of interceptor.
Example
_(' abc ')
.chain()
.trim()
.thru(function(value) {
return [value];
})
.value();
// => ['abc']
# static thru(value, interceptor) → {*}
This method is like _.tap except that it returns the result of interceptor.
The purpose of this method is to "pass thru" values replacing intermediate
results in a method chain sequence.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to provide to |
interceptor |
function | The function to invoke. |
- Since:
- 3.0.0
Returns the result of interceptor.
Example
_(' abc ')
.chain()
.trim()
.thru(function(value) {
return [value];
})
.value();
// => ['abc']
# static thru(value, interceptor) → {*}
This method is like _.tap except that it returns the result of interceptor.
The purpose of this method is to "pass thru" values replacing intermediate
results in a method chain sequence.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to provide to |
interceptor |
function | The function to invoke. |
- Since:
- 3.0.0
Returns the result of interceptor.
Example
_(' abc ')
.chain()
.trim()
.thru(function(value) {
return [value];
})
.value();
// => ['abc']
# static times(n, iterateeopt) → {Array}
Invokes the iteratee n times, returning an array of the results of
each invocation. The iteratee is invoked with one argument; (index).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
n |
number | The number of times to invoke |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
Returns the array of results.
Example
_.times(3, String);
// => ['0', '1', '2']
_.times(4, _.constant(0));
// => [0, 0, 0, 0]
# static times(n, iterateeopt) → {Array}
Invokes the iteratee n times, returning an array of the results of
each invocation. The iteratee is invoked with one argument; (index).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
n |
number | The number of times to invoke |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
- Since:
- 0.1.0
Returns the array of results.
Example
_.times(3, String);
// => ['0', '1', '2']
_.times(4, _.constant(0));
// => [0, 0, 0, 0]
# static toArray(value) → {Array}
Converts value to an array.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 0.1.0
Returns the converted array.
Example
_.toArray({ 'a': 1, 'b': 2 });
// => [1, 2]
_.toArray('abc');
// => ['a', 'b', 'c']
_.toArray(1);
// => []
_.toArray(null);
// => []
# static toArray(value) → {Array}
Converts value to an array.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 0.1.0
Returns the converted array.
Example
_.toArray({ 'a': 1, 'b': 2 });
// => [1, 2]
_.toArray('abc');
// => ['a', 'b', 'c']
_.toArray(1);
// => []
_.toArray(null);
// => []
# static toArray(value) → {Array}
Converts value to an array.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 0.1.0
Returns the converted array.
Example
_.toArray({ 'a': 1, 'b': 2 });
// => [1, 2]
_.toArray('abc');
// => ['a', 'b', 'c']
_.toArray(1);
// => []
_.toArray(null);
// => []
# static toFinite(value) → {number}
Converts value to a finite number.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 4.12.0
Returns the converted number.
Example
_.toFinite(3.2);
// => 3.2
_.toFinite(Number.MIN_VALUE);
// => 5e-324
_.toFinite(Infinity);
// => 1.7976931348623157e+308
_.toFinite('3.2');
// => 3.2
# static toFinite(value) → {number}
Converts value to a finite number.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 4.12.0
Returns the converted number.
Example
_.toFinite(3.2);
// => 3.2
_.toFinite(Number.MIN_VALUE);
// => 5e-324
_.toFinite(Infinity);
// => 1.7976931348623157e+308
_.toFinite('3.2');
// => 3.2
# static toInteger(value) → {number}
Converts value to an integer.
Note: This method is loosely based on
ToInteger.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 4.0.0
Returns the converted integer.
Example
_.toInteger(3.2);
// => 3
_.toInteger(Number.MIN_VALUE);
// => 0
_.toInteger(Infinity);
// => 1.7976931348623157e+308
_.toInteger('3.2');
// => 3
# static toInteger(value) → {number}
Converts value to an integer.
Note: This method is loosely based on
ToInteger.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 4.0.0
Returns the converted integer.
Example
_.toInteger(3.2);
// => 3
_.toInteger(Number.MIN_VALUE);
// => 0
_.toInteger(Infinity);
// => 1.7976931348623157e+308
_.toInteger('3.2');
// => 3
# static toLength(value) → {number}
Converts value to an integer suitable for use as the length of an
array-like object.
Note: This method is based on
ToLength.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 4.0.0
Returns the converted integer.
Example
_.toLength(3.2);
// => 3
_.toLength(Number.MIN_VALUE);
// => 0
_.toLength(Infinity);
// => 4294967295
_.toLength('3.2');
// => 3
# static toLength(value) → {number}
Converts value to an integer suitable for use as the length of an
array-like object.
Note: This method is based on
ToLength.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 4.0.0
Returns the converted integer.
Example
_.toLength(3.2);
// => 3
_.toLength(Number.MIN_VALUE);
// => 0
_.toLength(Infinity);
// => 4294967295
_.toLength('3.2');
// => 3
# static toLower(stringopt) → {string}
Converts string, as a whole, to lower case just like
String#toLowerCase.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to convert. |
- Since:
- 4.0.0
Returns the lower cased string.
Example
_.toLower('--Foo-Bar--');
// => '--foo-bar--'
_.toLower('fooBar');
// => 'foobar'
_.toLower('__FOO_BAR__');
// => '__foo_bar__'
# static toLower(stringopt) → {string}
Converts string, as a whole, to lower case just like
String#toLowerCase.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to convert. |
- Since:
- 4.0.0
Returns the lower cased string.
Example
_.toLower('--Foo-Bar--');
// => '--foo-bar--'
_.toLower('fooBar');
// => 'foobar'
_.toLower('__FOO_BAR__');
// => '__foo_bar__'
# static toNumber(value) → {number}
Converts value to a number.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to process. |
- Since:
- 4.0.0
Returns the number.
Example
_.toNumber(3.2);
// => 3.2
_.toNumber(Number.MIN_VALUE);
// => 5e-324
_.toNumber(Infinity);
// => Infinity
_.toNumber('3.2');
// => 3.2
# static toNumber(value) → {number}
Converts value to a number.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to process. |
- Since:
- 4.0.0
Returns the number.
Example
_.toNumber(3.2);
// => 3.2
_.toNumber(Number.MIN_VALUE);
// => 5e-324
_.toNumber(Infinity);
// => Infinity
_.toNumber('3.2');
// => 3.2
# static toPath(value) → {Array}
Converts value to a property path array.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 4.0.0
Returns the new property path array.
Example
_.toPath('a.b.c');
// => ['a', 'b', 'c']
_.toPath('a[0].b.c');
// => ['a', '0', 'b', 'c']
# static toPath(value) → {Array}
Converts value to a property path array.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 4.0.0
Returns the new property path array.
Example
_.toPath('a.b.c');
// => ['a', 'b', 'c']
_.toPath('a[0].b.c');
// => ['a', '0', 'b', 'c']
# static toPlainObject(value) → {Object}
Converts value to a plain object flattening inherited enumerable string
keyed properties of value to own properties of the plain object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 3.0.0
Returns the converted plain object.
Example
function Foo() {
this.b = 2;
}
Foo.prototype.c = 3;
_.assign({ 'a': 1 }, new Foo);
// => { 'a': 1, 'b': 2 }
_.assign({ 'a': 1 }, _.toPlainObject(new Foo));
// => { 'a': 1, 'b': 2, 'c': 3 }
# static toPlainObject(value) → {Object}
Converts value to a plain object flattening inherited enumerable string
keyed properties of value to own properties of the plain object.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 3.0.0
Returns the converted plain object.
Example
function Foo() {
this.b = 2;
}
Foo.prototype.c = 3;
_.assign({ 'a': 1 }, new Foo);
// => { 'a': 1, 'b': 2 }
_.assign({ 'a': 1 }, _.toPlainObject(new Foo));
// => { 'a': 1, 'b': 2, 'c': 3 }
# static toSafeInteger(value) → {number}
Converts value to a safe integer. A safe integer can be compared and
represented correctly.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 4.0.0
Returns the converted integer.
Example
_.toSafeInteger(3.2);
// => 3
_.toSafeInteger(Number.MIN_VALUE);
// => 0
_.toSafeInteger(Infinity);
// => 9007199254740991
_.toSafeInteger('3.2');
// => 3
# static toSafeInteger(value) → {number}
Converts value to a safe integer. A safe integer can be compared and
represented correctly.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 4.0.0
Returns the converted integer.
Example
_.toSafeInteger(3.2);
// => 3
_.toSafeInteger(Number.MIN_VALUE);
// => 0
_.toSafeInteger(Infinity);
// => 9007199254740991
_.toSafeInteger('3.2');
// => 3
# static toString(value) → {string}
Converts value to a string. An empty string is returned for null
and undefined values. The sign of -0 is preserved.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 4.0.0
Returns the converted string.
Example
_.toString(null);
// => ''
_.toString(-0);
// => '-0'
_.toString([1, 2, 3]);
// => '1,2,3'
# static toString(value) → {string}
Converts value to a string. An empty string is returned for null
and undefined values. The sign of -0 is preserved.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 4.0.0
Returns the converted string.
Example
_.toString(null);
// => ''
_.toString(-0);
// => '-0'
_.toString([1, 2, 3]);
// => '1,2,3'
# static toString(value) → {string}
Converts value to a string. An empty string is returned for null
and undefined values. The sign of -0 is preserved.
Parameters:
| Name | Type | Description |
|---|---|---|
value |
* | The value to convert. |
- Since:
- 4.0.0
Returns the converted string.
Example
_.toString(null);
// => ''
_.toString(-0);
// => '-0'
_.toString([1, 2, 3]);
// => '1,2,3'
# static toUpper(stringopt) → {string}
Converts string, as a whole, to upper case just like
String#toUpperCase.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to convert. |
- Since:
- 4.0.0
Returns the upper cased string.
Example
_.toUpper('--foo-bar--');
// => '--FOO-BAR--'
_.toUpper('fooBar');
// => 'FOOBAR'
_.toUpper('__foo_bar__');
// => '__FOO_BAR__'
# static toUpper(stringopt) → {string}
Converts string, as a whole, to upper case just like
String#toUpperCase.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to convert. |
- Since:
- 4.0.0
Returns the upper cased string.
Example
_.toUpper('--foo-bar--');
// => '--FOO-BAR--'
_.toUpper('fooBar');
// => 'FOOBAR'
_.toUpper('__foo_bar__');
// => '__FOO_BAR__'
# static transform(object, iterateeopt, accumulatoropt) → {*}
An alternative to _.reduce; this method transforms object to a new
accumulator object which is the result of running each of its own
enumerable string keyed properties thru iteratee, with each invocation
potentially mutating the accumulator object. If accumulator is not
provided, a new object with the same [[Prototype]] will be used. The
iteratee is invoked with four arguments: (accumulator, value, key, object).
Iteratee functions may exit iteration early by explicitly returning false.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
accumulator |
* |
<optional> |
The custom accumulator value. |
- Since:
- 1.3.0
Returns the accumulated value.
Example
_.transform([2, 3, 4], function(result, n) {
result.push(n *= n);
return n % 2 == 0;
}, []);
// => [4, 9]
_.transform({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) {
(result[value] || (result[value] = [])).push(key);
}, {});
// => { '1': ['a', 'c'], '2': ['b'] }
# static transform(object, iterateeopt, accumulatoropt) → {*}
An alternative to _.reduce; this method transforms object to a new
accumulator object which is the result of running each of its own
enumerable string keyed properties thru iteratee, with each invocation
potentially mutating the accumulator object. If accumulator is not
provided, a new object with the same [[Prototype]] will be used. The
iteratee is invoked with four arguments: (accumulator, value, key, object).
Iteratee functions may exit iteration early by explicitly returning false.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
object |
Object | The object to iterate over. |
||
iteratee |
function |
<optional> |
_.identity | The function invoked per iteration. |
accumulator |
* |
<optional> |
The custom accumulator value. |
- Since:
- 1.3.0
Returns the accumulated value.
Example
_.transform([2, 3, 4], function(result, n) {
result.push(n *= n);
return n % 2 == 0;
}, []);
// => [4, 9]
_.transform({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) {
(result[value] || (result[value] = [])).push(key);
}, {});
// => { '1': ['a', 'c'], '2': ['b'] }
# static trim(stringopt, charsopt) → {string}
Removes leading and trailing whitespace or specified characters from string.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to trim. |
chars |
string |
<optional> |
whitespace | The characters to trim. |
- Since:
- 3.0.0
Returns the trimmed string.
Example
_.trim(' abc ');
// => 'abc'
_.trim('-_-abc-_-', '_-');
// => 'abc'
_.map([' foo ', ' bar '], _.trim);
// => ['foo', 'bar']
# static trim(stringopt, charsopt) → {string}
Removes leading and trailing whitespace or specified characters from string.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to trim. |
chars |
string |
<optional> |
whitespace | The characters to trim. |
- Since:
- 3.0.0
Returns the trimmed string.
Example
_.trim(' abc ');
// => 'abc'
_.trim('-_-abc-_-', '_-');
// => 'abc'
_.map([' foo ', ' bar '], _.trim);
// => ['foo', 'bar']
# static trimEnd(stringopt, charsopt) → {string}
Removes trailing whitespace or specified characters from string.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to trim. |
chars |
string |
<optional> |
whitespace | The characters to trim. |
- Since:
- 4.0.0
Returns the trimmed string.
Example
_.trimEnd(' abc ');
// => ' abc'
_.trimEnd('-_-abc-_-', '_-');
// => '-_-abc'
# static trimEnd(stringopt, charsopt) → {string}
Removes trailing whitespace or specified characters from string.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to trim. |
chars |
string |
<optional> |
whitespace | The characters to trim. |
- Since:
- 4.0.0
Returns the trimmed string.
Example
_.trimEnd(' abc ');
// => ' abc'
_.trimEnd('-_-abc-_-', '_-');
// => '-_-abc'
# static trimStart(stringopt, charsopt) → {string}
Removes leading whitespace or specified characters from string.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to trim. |
chars |
string |
<optional> |
whitespace | The characters to trim. |
- Since:
- 4.0.0
Returns the trimmed string.
Example
_.trimStart(' abc ');
// => 'abc '
_.trimStart('-_-abc-_-', '_-');
// => 'abc-_-'
# static trimStart(stringopt, charsopt) → {string}
Removes leading whitespace or specified characters from string.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to trim. |
chars |
string |
<optional> |
whitespace | The characters to trim. |
- Since:
- 4.0.0
Returns the trimmed string.
Example
_.trimStart(' abc ');
// => 'abc '
_.trimStart('-_-abc-_-', '_-');
// => 'abc-_-'
# static truncate(stringopt, optionsopt) → {string}
Truncates string if it's longer than the given maximum string length.
The last characters of the truncated string are replaced with the omission
string which defaults to "...".
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to truncate. |
options |
Object |
<optional> |
{} | The options object. |
length |
number |
<optional> |
30 | The maximum string length. |
omission |
string |
<optional> |
'...' | The string to indicate text is omitted. |
separator |
RegExp | string |
<optional> |
The separator pattern to truncate to. |
- Since:
- 4.0.0
Returns the truncated string.
Example
_.truncate('hi-diddly-ho there, neighborino');
// => 'hi-diddly-ho there, neighbo...'
_.truncate('hi-diddly-ho there, neighborino', {
'length': 24,
'separator': ' '
});
// => 'hi-diddly-ho there,...'
_.truncate('hi-diddly-ho there, neighborino', {
'length': 24,
'separator': /,? +/
});
// => 'hi-diddly-ho there...'
_.truncate('hi-diddly-ho there, neighborino', {
'omission': ' [...]'
});
// => 'hi-diddly-ho there, neig [...]'
# static truncate(stringopt, optionsopt) → {string}
Truncates string if it's longer than the given maximum string length.
The last characters of the truncated string are replaced with the omission
string which defaults to "...".
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to truncate. |
options |
Object |
<optional> |
{} | The options object. |
length |
number |
<optional> |
30 | The maximum string length. |
omission |
string |
<optional> |
'...' | The string to indicate text is omitted. |
separator |
RegExp | string |
<optional> |
The separator pattern to truncate to. |
- Since:
- 4.0.0
Returns the truncated string.
Example
_.truncate('hi-diddly-ho there, neighborino');
// => 'hi-diddly-ho there, neighbo...'
_.truncate('hi-diddly-ho there, neighborino', {
'length': 24,
'separator': ' '
});
// => 'hi-diddly-ho there,...'
_.truncate('hi-diddly-ho there, neighborino', {
'length': 24,
'separator': /,? +/
});
// => 'hi-diddly-ho there...'
_.truncate('hi-diddly-ho there, neighborino', {
'omission': ' [...]'
});
// => 'hi-diddly-ho there, neig [...]'
# static unary(func) → {function}
Creates a function that accepts up to one argument, ignoring any additional arguments.
Parameters:
| Name | Type | Description |
|---|---|---|
func |
function | The function to cap arguments for. |
- Since:
- 4.0.0
Returns the new capped function.
Example
_.map(['6', '8', '10'], _.unary(parseInt));
// => [6, 8, 10]
# static unary(func) → {function}
Creates a function that accepts up to one argument, ignoring any additional arguments.
Parameters:
| Name | Type | Description |
|---|---|---|
func |
function | The function to cap arguments for. |
- Since:
- 4.0.0
Returns the new capped function.
Example
_.map(['6', '8', '10'], _.unary(parseInt));
// => [6, 8, 10]
# static unescape(stringopt) → {string}
The inverse of _.escape; this method converts the HTML entities
&, <, >, ", and ' in string to
their corresponding characters.
Note: No other HTML entities are unescaped. To unescape additional HTML entities use a third-party library like he.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to unescape. |
- Since:
- 0.6.0
Returns the unescaped string.
Example
_.unescape('fred, barney, & pebbles');
// => 'fred, barney, & pebbles'
# static unescape(stringopt) → {string}
The inverse of _.escape; this method converts the HTML entities
&, <, >, ", and ' in string to
their corresponding characters.
Note: No other HTML entities are unescaped. To unescape additional HTML entities use a third-party library like he.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to unescape. |
- Since:
- 0.6.0
Returns the unescaped string.
Example
_.unescape('fred, barney, & pebbles');
// => 'fred, barney, & pebbles'
# static uniq(array) → {Array}
Creates a duplicate-free version of an array, using
SameValueZero
for equality comparisons, in which only the first occurrence of each element
is kept. The order of result values is determined by the order they occur
in the array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to inspect. |
- Since:
- 0.1.0
Returns the new duplicate free array.
Example
_.uniq([2, 1, 2]);
// => [2, 1]
# static uniq(array) → {Array}
Creates a duplicate-free version of an array, using
SameValueZero
for equality comparisons, in which only the first occurrence of each element
is kept. The order of result values is determined by the order they occur
in the array.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array to inspect. |
- Since:
- 0.1.0
Returns the new duplicate free array.
Example
_.uniq([2, 1, 2]);
// => [2, 1]
# static uniqBy(array, iterateeopt) → {Array}
This method is like _.uniq except that it accepts iteratee which is
invoked for each element in array to generate the criterion by which
uniqueness is computed. The order of result values is determined by the
order they occur in the array. The iteratee is invoked with one argument:
(value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to inspect. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.0.0
Returns the new duplicate free array.
Example
_.uniqBy([2.1, 1.2, 2.3], Math.floor);
// => [2.1, 1.2]
// The `_.property` iteratee shorthand.
_.uniqBy([{ 'x': 1 }, { 'x': 2 }, { 'x': 1 }], 'x');
// => [{ 'x': 1 }, { 'x': 2 }]
# static uniqBy(array, iterateeopt) → {Array}
This method is like _.uniq except that it accepts iteratee which is
invoked for each element in array to generate the criterion by which
uniqueness is computed. The order of result values is determined by the
order they occur in the array. The iteratee is invoked with one argument:
(value).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array to inspect. |
||
iteratee |
function |
<optional> |
_.identity | The iteratee invoked per element. |
- Since:
- 4.0.0
Returns the new duplicate free array.
Example
_.uniqBy([2.1, 1.2, 2.3], Math.floor);
// => [2.1, 1.2]
// The `_.property` iteratee shorthand.
_.uniqBy([{ 'x': 1 }, { 'x': 2 }, { 'x': 1 }], 'x');
// => [{ 'x': 1 }, { 'x': 2 }]
# static uniqueId(prefixopt) → {string}
Generates a unique ID. If prefix is given, the ID is appended to it.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
prefix |
string |
<optional> |
'' | The value to prefix the ID with. |
- Since:
- 0.1.0
Returns the unique ID.
Example
_.uniqueId('contact_');
// => 'contact_104'
_.uniqueId();
// => '105'
# static uniqueId(prefixopt) → {string}
Generates a unique ID. If prefix is given, the ID is appended to it.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
prefix |
string |
<optional> |
'' | The value to prefix the ID with. |
- Since:
- 0.1.0
Returns the unique ID.
Example
_.uniqueId('contact_');
// => 'contact_104'
_.uniqueId();
// => '105'
# static uniqueId(prefixopt) → {string}
Generates a unique ID. If prefix is given, the ID is appended to it.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
prefix |
string |
<optional> |
'' | The value to prefix the ID with. |
- Since:
- 0.1.0
Returns the unique ID.
Example
_.uniqueId('contact_');
// => 'contact_104'
_.uniqueId();
// => '105'
# static uniqWith(array, comparatoropt) → {Array}
This method is like _.uniq except that it accepts comparator which
is invoked to compare elements of array. The order of result values is
determined by the order they occur in the array.The comparator is invoked
with two arguments: (arrVal, othVal).
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
array |
Array | The array to inspect. |
|
comparator |
function |
<optional> |
The comparator invoked per element. |
- Since:
- 4.0.0
Returns the new duplicate free array.
Example
var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }, { 'x': 1, 'y': 2 }];
_.uniqWith(objects, _.isEqual);
// => [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }]
# static uniqWith(array, comparatoropt) → {Array}
This method is like _.uniq except that it accepts comparator which
is invoked to compare elements of array. The order of result values is
determined by the order they occur in the array.The comparator is invoked
with two arguments: (arrVal, othVal).
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
array |
Array | The array to inspect. |
|
comparator |
function |
<optional> |
The comparator invoked per element. |
- Since:
- 4.0.0
Returns the new duplicate free array.
Example
var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }, { 'x': 1, 'y': 2 }];
_.uniqWith(objects, _.isEqual);
// => [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }]
# static unset(object, path) → {boolean}
Removes the property at path of object.
Note: This method mutates object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to modify. |
path |
Array | string | The path of the property to unset. |
- Since:
- 4.0.0
Returns true if the property is deleted, else false.
Example
var object = { 'a': [{ 'b': { 'c': 7 } }] };
_.unset(object, 'a[0].b.c');
// => true
console.log(object);
// => { 'a': [{ 'b': {} }] };
_.unset(object, ['a', '0', 'b', 'c']);
// => true
console.log(object);
// => { 'a': [{ 'b': {} }] };
# static unset(object, path) → {boolean}
Removes the property at path of object.
Note: This method mutates object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to modify. |
path |
Array | string | The path of the property to unset. |
- Since:
- 4.0.0
Returns true if the property is deleted, else false.
Example
var object = { 'a': [{ 'b': { 'c': 7 } }] };
_.unset(object, 'a[0].b.c');
// => true
console.log(object);
// => { 'a': [{ 'b': {} }] };
_.unset(object, ['a', '0', 'b', 'c']);
// => true
console.log(object);
// => { 'a': [{ 'b': {} }] };
# static unzip(array) → {Array}
This method is like _.zip except that it accepts an array of grouped
elements and creates an array regrouping the elements to their pre-zip
configuration.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array of grouped elements to process. |
- Since:
- 1.2.0
Returns the new array of regrouped elements.
Example
var zipped = _.zip(['a', 'b'], [1, 2], [true, false]);
// => [['a', 1, true], ['b', 2, false]]
_.unzip(zipped);
// => [['a', 'b'], [1, 2], [true, false]]
# static unzip(array) → {Array}
This method is like _.zip except that it accepts an array of grouped
elements and creates an array regrouping the elements to their pre-zip
configuration.
Parameters:
| Name | Type | Description |
|---|---|---|
array |
Array | The array of grouped elements to process. |
- Since:
- 1.2.0
Returns the new array of regrouped elements.
Example
var zipped = _.zip(['a', 'b'], [1, 2], [true, false]);
// => [['a', 1, true], ['b', 2, false]]
_.unzip(zipped);
// => [['a', 'b'], [1, 2], [true, false]]
# static unzipWith(array, iterateeopt) → {Array}
This method is like _.unzip except that it accepts iteratee to specify
how regrouped values should be combined. The iteratee is invoked with the
elements of each group: (...group).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array of grouped elements to process. |
||
iteratee |
function |
<optional> |
_.identity | The function to combine regrouped values. |
- Since:
- 3.8.0
Returns the new array of regrouped elements.
Example
var zipped = _.zip([1, 2], [10, 20], [100, 200]);
// => [[1, 10, 100], [2, 20, 200]]
_.unzipWith(zipped, _.add);
// => [3, 30, 300]
# static unzipWith(array, iterateeopt) → {Array}
This method is like _.unzip except that it accepts iteratee to specify
how regrouped values should be combined. The iteratee is invoked with the
elements of each group: (...group).
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
array |
Array | The array of grouped elements to process. |
||
iteratee |
function |
<optional> |
_.identity | The function to combine regrouped values. |
- Since:
- 3.8.0
Returns the new array of regrouped elements.
Example
var zipped = _.zip([1, 2], [10, 20], [100, 200]);
// => [[1, 10, 100], [2, 20, 200]]
_.unzipWith(zipped, _.add);
// => [3, 30, 300]
# static update(object, path, updater) → {Object}
This method is like _.set except that accepts updater to produce the
value to set. Use _.updateWith to customize path creation. The updater
is invoked with one argument: (value).
Note: This method mutates object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to modify. |
path |
Array | string | The path of the property to set. |
updater |
function | The function to produce the updated value. |
- Since:
- 4.6.0
Returns object.
Example
var object = { 'a': [{ 'b': { 'c': 3 } }] };
_.update(object, 'a[0].b.c', function(n) { return n * n; });
console.log(object.a[0].b.c);
// => 9
_.update(object, 'x[0].y.z', function(n) { return n ? n + 1 : 0; });
console.log(object.x[0].y.z);
// => 0
# static update(object, path, updater) → {Object}
This method is like _.set except that accepts updater to produce the
value to set. Use _.updateWith to customize path creation. The updater
is invoked with one argument: (value).
Note: This method mutates object.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to modify. |
path |
Array | string | The path of the property to set. |
updater |
function | The function to produce the updated value. |
- Since:
- 4.6.0
Returns object.
Example
var object = { 'a': [{ 'b': { 'c': 3 } }] };
_.update(object, 'a[0].b.c', function(n) { return n * n; });
console.log(object.a[0].b.c);
// => 9
_.update(object, 'x[0].y.z', function(n) { return n ? n + 1 : 0; });
console.log(object.x[0].y.z);
// => 0
# static updateWith(object, path, updater, customizeropt) → {Object}
This method is like _.update except that it accepts customizer which is
invoked to produce the objects of path. If customizer returns undefined
path creation is handled by the method instead. The customizer is invoked
with three arguments: (nsValue, key, nsObject).
Note: This method mutates object.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
object |
Object | The object to modify. |
|
path |
Array | string | The path of the property to set. |
|
updater |
function | The function to produce the updated value. |
|
customizer |
function |
<optional> |
The function to customize assigned values. |
- Since:
- 4.6.0
Returns object.
Example
var object = {};
_.updateWith(object, '[0][1]', _.constant('a'), Object);
// => { '0': { '1': 'a' } }
# static updateWith(object, path, updater, customizeropt) → {Object}
This method is like _.update except that it accepts customizer which is
invoked to produce the objects of path. If customizer returns undefined
path creation is handled by the method instead. The customizer is invoked
with three arguments: (nsValue, key, nsObject).
Note: This method mutates object.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
object |
Object | The object to modify. |
|
path |
Array | string | The path of the property to set. |
|
updater |
function | The function to produce the updated value. |
|
customizer |
function |
<optional> |
The function to customize assigned values. |
- Since:
- 4.6.0
Returns object.
Example
var object = {};
_.updateWith(object, '[0][1]', _.constant('a'), Object);
// => { '0': { '1': 'a' } }
# static values(object) → {Array}
Creates an array of the own enumerable string keyed property values of object.
Note: Non-object values are coerced to objects.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
- Since:
- 0.1.0
Returns the array of property values.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.values(new Foo);
// => [1, 2] (iteration order is not guaranteed)
_.values('hi');
// => ['h', 'i']
# static values(object) → {Array}
Creates an array of the own enumerable string keyed property values of object.
Note: Non-object values are coerced to objects.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
- Since:
- 0.1.0
Returns the array of property values.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.values(new Foo);
// => [1, 2] (iteration order is not guaranteed)
_.values('hi');
// => ['h', 'i']
# static values(object) → {Array}
Creates an array of the own enumerable string keyed property values of object.
Note: Non-object values are coerced to objects.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
- Since:
- 0.1.0
Returns the array of property values.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.values(new Foo);
// => [1, 2] (iteration order is not guaranteed)
_.values('hi');
// => ['h', 'i']
# static valuesIn(object) → {Array}
Creates an array of the own and inherited enumerable string keyed property
values of object.
Note: Non-object values are coerced to objects.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
- Since:
- 3.0.0
Returns the array of property values.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.valuesIn(new Foo);
// => [1, 2, 3] (iteration order is not guaranteed)
# static valuesIn(object) → {Array}
Creates an array of the own and inherited enumerable string keyed property
values of object.
Note: Non-object values are coerced to objects.
Parameters:
| Name | Type | Description |
|---|---|---|
object |
Object | The object to query. |
- Since:
- 3.0.0
Returns the array of property values.
Example
function Foo() {
this.a = 1;
this.b = 2;
}
Foo.prototype.c = 3;
_.valuesIn(new Foo);
// => [1, 2, 3] (iteration order is not guaranteed)
# static words(stringopt, patternopt) → {Array}
Splits string into an array of its words.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to inspect. |
pattern |
RegExp | string |
<optional> |
The pattern to match words. |
- Since:
- 3.0.0
Returns the words of string.
Example
_.words('fred, barney, & pebbles');
// => ['fred', 'barney', 'pebbles']
_.words('fred, barney, & pebbles', /[^, ]+/g);
// => ['fred', 'barney', '&', 'pebbles']
# static words(stringopt, patternopt) → {Array}
Splits string into an array of its words.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
string |
string |
<optional> |
'' | The string to inspect. |
pattern |
RegExp | string |
<optional> |
The pattern to match words. |
- Since:
- 3.0.0
Returns the words of string.
Example
_.words('fred, barney, & pebbles');
// => ['fred', 'barney', 'pebbles']
_.words('fred, barney, & pebbles', /[^, ]+/g);
// => ['fred', 'barney', '&', 'pebbles']
# static wrap(value, wrapperopt) → {function}
Creates a function that provides value to wrapper as its first
argument. Any additional arguments provided to the function are appended
to those provided to the wrapper. The wrapper is invoked with the this
binding of the created function.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
value |
* | The value to wrap. |
||
wrapper |
function |
<optional> |
identity | The wrapper function. |
- Since:
- 0.1.0
Returns the new function.
Example
var p = _.wrap(_.escape, function(func, text) {
return '<p>' + func(text) + '</p>';
});
p('fred, barney, & pebbles');
// => '<p>fred, barney, & pebbles</p>'
# static wrap(value, wrapperopt) → {function}
Creates a function that provides value to wrapper as its first
argument. Any additional arguments provided to the function are appended
to those provided to the wrapper. The wrapper is invoked with the this
binding of the created function.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
value |
* | The value to wrap. |
||
wrapper |
function |
<optional> |
identity | The wrapper function. |
- Since:
- 0.1.0
Returns the new function.
Example
var p = _.wrap(_.escape, function(func, text) {
return '<p>' + func(text) + '</p>';
});
p('fred, barney, & pebbles');
// => '<p>fred, barney, & pebbles</p>'
# static zipObject(propsopt, valuesopt) → {Object}
This method is like _.fromPairs except that it accepts two arrays,
one of property identifiers and one of corresponding values.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
props |
Array |
<optional> |
[] | The property identifiers. |
values |
Array |
<optional> |
[] | The property values. |
- Since:
- 0.4.0
Returns the new object.
Example
_.zipObject(['a', 'b'], [1, 2]);
// => { 'a': 1, 'b': 2 }
# static zipObject(propsopt, valuesopt) → {Object}
This method is like _.fromPairs except that it accepts two arrays,
one of property identifiers and one of corresponding values.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
props |
Array |
<optional> |
[] | The property identifiers. |
values |
Array |
<optional> |
[] | The property values. |
- Since:
- 0.4.0
Returns the new object.
Example
_.zipObject(['a', 'b'], [1, 2]);
// => { 'a': 1, 'b': 2 }
# static zipObjectDeep(propsopt, valuesopt) → {Object}
This method is like _.zipObject except that it supports property paths.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
props |
Array |
<optional> |
[] | The property identifiers. |
values |
Array |
<optional> |
[] | The property values. |
- Since:
- 4.1.0
Returns the new object.
Example
_.zipObjectDeep(['a.b[0].c', 'a.b[1].d'], [1, 2]);
// => { 'a': { 'b': [{ 'c': 1 }, { 'd': 2 }] } }
# static zipObjectDeep(propsopt, valuesopt) → {Object}
This method is like _.zipObject except that it supports property paths.
Parameters:
| Name | Type | Attributes | Default | Description |
|---|---|---|---|---|
props |
Array |
<optional> |
[] | The property identifiers. |
values |
Array |
<optional> |
[] | The property values. |
- Since:
- 4.1.0
Returns the new object.
Example
_.zipObjectDeep(['a.b[0].c', 'a.b[1].d'], [1, 2]);
// => { 'a': { 'b': [{ 'c': 1 }, { 'd': 2 }] } }